The Complete IB Biology Syllabus SL and HL

The Complete IB Biology Syllabus SL and HL SAT / ACT Prep Online Guides and Tips Oh, IB Biology. I took IB Biology SL back in my high school days. If you are looking at this syllabus, you're likely interested in taking the course or are currently enrolled in the course. In this article, I will go over the topics covered in IB Biology Standard Level and IB Biology Higher Level, as well as the number of hours dedicated to each topic along with what the IB expects you to understand for each topic. IB Biology SL and HL Core Both IB Biology SL and HL consist of the same core requirements (95 hours). Both classes cover the same six topics in the order listed below with the same subtopics listed below: Topic 1: Cell Biology- 15 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Introduction to cells 1.1 According to the cell theory, living organisms are composed of cells. Organisms consisting of only one cell carry out all functions of life in that cell. Surface area to volume ratio is important in the limitation of cell size. Multicellular organisms have properties that emerge from the interaction of their cellular components. Specialized tissues can develop by cell differentiation in multicellular organisms. Differentiation involves the expression of some genes and not others in a cell’s genome. The capacity of stem cells to divide and differentiate along different pathways is necessary in embryonic development and also makes stem cells suitable for therapeutic uses. Ultrastructure of cells 1.2 Prokaryotes have a simple cell structure without compartmentalization. Eukaryotes have a compartmentalized cell structure. Electron microscopes have a much higher resolution than light microscopes. Membrane structure 1.3 Phospholipids form bilayers in water due to the amphipathic properties of phospholipid molecules. Membrane proteins are diverse in terms of structure, position in the membrane and function. Cholesterol is a component of animal cell membranes. Membrane transport 1.4 Particles move across membranes by simple diffusion, facilitated diffusion, osmosis and active transport. The fluidity of membranes allows materials to be taken into cells by endocytosis or released by exocytosis. Vesicles move materials within cells. The origin of cells 1.5 Cells can only be formed by division of pre-existing cells. The first cells must have arisen from non-living material. The origin of eukaryotic cells can be explained by the endosymbiotic theory. Cell division 1.6 Mitosis is division of the nucleus into two genetically identical daughter nuclei. Chromosomes condense by supercoiling during mitosis. Cytokinesis occurs after mitosis and is different in plant and animal cells. Interphase is a very active phase of the cell cycle with many processes occurring in the nucleus and cytoplasm. Cyclins are involved in the control of the cell cycle. Mutagens, oncogenes and metastasis are involved in the development of primary and secondary tumours. Want to get better grades and test scores? We can help. PrepScholar Tutors is the world's best tutoring service. We combine world-class expert tutors with our proprietary teaching techniques. Our students have gotten A's on thousands of classes, perfect 5's on AP tests, and ludicrously high SAT Subject Test scores. Whether you need help with science, math, English, social science, or more, we've got you covered. Get better grades today with PrepScholar Tutors. Topic 2: Molecular Biology- 21 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Molecules to metabolism 2.1 Molecular biology explains living processes in terms of the chemical substances involved. Carbon atoms can form four covalent bonds allowing a diversity of stable compounds to exist. Life is based on carbon compounds including carbohydrates, lipids, proteins and nucleic acids. Metabolism is the web of all the enzyme-catalysed reactions in a cell or organism. Anabolism is the synthesis of complex molecules from simpler molecules including the formation of macromolecules from monomers by condensation reactions. Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers. Water 2.2 Water molecules are polar and hydrogen bonds form between them. Hydrogen bonding and dipolarity explain the cohesive, adhesive, thermal and solvent properties of water. Substances can be hydrophilic or hydrophobic. Carbohydrates and lipids 2.3 Monosaccharide monomers are linked together by condensation reactions to form disaccharides and polysaccharide polymers. Fatty acids can be saturated, monounsaturated or polyunsaturated. Unsaturated fatty acids can be cis or trans isomers. Triglycerides are formed by condensation from three fatty acids and one glycerol. Proteins 2.4 Amino acids are linked together by condensation to form polypeptides. There are 20 different amino acids in polypeptides synthesized on ribosomes. Amino acids can be linked together in any sequence giving a huge range of possible polypeptides. The amino acid sequence of polypeptides is coded for by genes. A protein may consist of a single polypeptide or more than one polypeptide linked together. The amino acid sequence determines the three-dimensional conformation of a protein. Living organisms synthesize many different proteins with a wide range of functions. Every individual has a unique proteome. Enzymes 2.5 Enzymes have an active site to which specific substrates bind. Enzyme catalysis involves molecular motion and the collision of substrates with the active site. Temperature, pH and substrate concentration affect the rate of activity of enzymes. Enzymes can be denatured. Immobilized enzymes are widely used in industry. Structure of DNA and RNA 2.6 The nucleic acids DNA and RNA are polymers of nucleotides. DNA differs from RNA in the number of strands present, the base composition and the type of pentose. DNA is a double helix made of two antiparallel strands of nucleotides linked by hydrogen bonding between complementary base pairs. DNA replication, transcription and translation 2.7 The replication of DNA is semi-conservative and depends on complementary base pairing. Helicase unwinds the double helix and separates the two strands by breaking hydrogen bonds. DNA polymerase links nucleotides together to form a new strand, using the pre-existing strand as a template. Transcription is the synthesis of mRNA copied from the DNA base sequences by RNA polymerase. Translation is the synthesis of polypeptides on ribosomes. The amino acid sequence of polypeptides is determined by mRNA according to the genetic code. Codons of three bases on mRNA correspond to one amino acid in a polypeptide. Translation depends on complementary base pairing between codons on mRNA and anticodons on tRNA. Cell respiration 2.8 Cell respiration is the controlled release of energy from organic compounds to produce ATP. ATP from cell respiration is immediately available as a source of energy in the cell. Anaerobic cell respiration gives a small yield of ATP from glucose. Aerobic cell respiration requires oxygen and gives a large yield of ATP from glucose. Photosynthesis 2.9 Photosynthesis is the production of carbon compounds in cells using light energy. Visible light has a range of wavelengths with violet the shortest wavelength and red the longest. Chlorophyll absorbs red and blue light most effectively and reflects green light more than other colours. Oxygen is produced in photosynthesis from the photolysis of water. Energy is needed to produce carbohydrates and other carbon compounds from carbon dioxide. Temperature, light intensity and carbon dioxide concentration are possible limiting factors on the rate of photosynthesis. Topic 3: Genetics- 15 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Genes 3.1 A gene is a heritable factor that consists of a length of DNA and influences a specific characteristic. A gene occupies a specific position on a chromosome. The various specific forms of a gene are alleles. Alleles differ from each other by one or only a few bases. New alleles are formed by mutation. The genome is the whole of the genetic information of an organism. The entire base sequence of human genes was sequenced in the Human Genome Project. Chromosomes 3.2 Prokaryotes have one chromosome consisting of a circular DNA molecule. Some prokaryotes also have plasmids but eukaryotes do not. Eukaryote chromosomes are linear DNA molecules associated with histone proteins. In a eukaryote species there are different chromosomes that carry different genes. Homologous chromosomes carry the same sequence of genes but not necessarily the same alleles of those genes. Diploid nuclei have pairs of homologous chromosomes. Haploid nuclei have one chromosome of each pair. The number of chromosomes is a characteristic feature of members of a species. A karyogram shows the chromosomes of an organism in homologous pairs of decreasing length. Sex is determined by sex chromosomes and autosomes are chromosomes that do not determine sex. Meiosis 3.3 One diploid nucleus divides by meiosis to produce four haploid nuclei. The halving of the chromosome number allows a sexual life cycle with fusion of gametes. DNA is replicated before meiosis so that all chromosomes consist of two sister chromatids. The early stages of meiosis involve pairing of homologous chromosomes and crossing over followed by condensation. Orientation of pairs of homologous chromosomes prior to separation is random. Separation of pairs of homologous chromosomes in the first division of meiosis halves the chromosome number. Crossing over and random orientation promotes genetic variation. Fusion of gametes from different parents promotes genetic variation. Inheritance 3.4 Mendel discovered the principles of inheritance with experiments in which large numbers of pea plants were crossed. Gametes are haploid so contain only one allele of each gene. The two alleles of each gene separate into different haploid daughter nuclei during meiosis. Fusion of gametes results in diploid zygotes with two alleles of each gene that may be the same allele or different alleles. Dominant alleles mask the effects of recessive alleles but co-dominant alleles have joint effects. Many genetic diseases in humans are due to recessive alleles of autosomal genes, although some genetic diseases are due to dominant or co-dominant alleles. Some genetic diseases are sex-linked. The pattern of inheritance is different with sex-linked genes due to their location on sex chromosomes. Many genetic diseases have been identified in humans but most are very rare. Radiation and mutagenic chemicals increase the mutation rate and can cause genetic diseases and cancer. Genetic modification and biotechnology 3.5 Gel electrophoresis is used to separate proteins or fragments of DNA according to size. PCR can be used to amplify small amounts of DNA. DNA profiling involves comparison of DNA. Genetic modification is carried out by gene transfer between species. Clones are groups of genetically identical organisms, derived from a single original parent cell. Many plant species and some animal species have natural methods of cloning. Animals can be cloned at the embryo stage by breaking up the embryo into more than one group of cells. Methods have been developed for cloning adult animals using differentiated cells. Topic 4: Ecology- 12 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Species, communities and ecosystems 4.1 Species are groups of organisms that can potentially interbreed to produce fertile offspring. Members of a species may be reproductively isolated in separate populations. Species have either an autotrophic or heterotrophic method of nutrition (a few species have both methods). Consumers are heterotrophs that feed on living organisms by ingestion. Detritivores are heterotrophs that obtain organic nutrients from detritus by internal digestion. Saprotrophs are heterotrophs that obtain organic nutrients from dead organisms by external digestion. A community is formed by populations of different species living together and interacting with each other. A community forms an ecosystem by its interactions with the abiotic environment. Autotrophs obtain inorganic nutrients from the abiotic environment. The supply of inorganic nutrients is maintained by nutrient cycling. Ecosystems have the potential to be sustainable over long periods of time. Energy flow 4.2 Most ecosystems rely on a supply of energy from sunlight. Light energy is converted to chemical energy in carbon compounds by photosynthesis. Chemical energy in carbon compounds flows through food chains by means of feeding. Energy released from carbon compounds by respiration is used in living organisms and converted to heat. Living organisms cannot convert heat to other forms of energy. Heat is lost from ecosystems. Energy losses between trophic levels restrict the length of food chains and the biomass of higher trophic levels. Carbon cycling 4.3 Autotrophs convert carbon dioxide into carbohydrates and other carbon compounds. In aquatic ecosystems carbon is present as dissolved carbon dioxide and hydrogen carbonate ions. Carbon dioxide diffuses from the atmosphere or water into autotrophs. Carbon dioxide is produced by respiration and diffuses out of organisms into water or the atmosphere. Methane is produced from organic matter in anaerobic conditions by methanogenic archaeans and some diffuses into the atmosphere or accumulates in the ground. Methane is oxidized to carbon dioxide and water in the atmosphere. Peat forms when organic matter is not fully decomposed because of acidic and/or anaerobic conditions in waterlogged soils. Partially decomposed organic matter from past geological eras was converted either into coal or into oil and gas that accumulate in porous rocks. Carbon dioxide is produced by the combustion of biomass and fossilized organic matter. Animals such as reef-building corals and mollusca have hard parts that are composed of calcium carbonate and can become fossilized in limestone. Climate change 4.4 Carbon dioxide and water vapour are the most significant greenhouse gases. Other gases including methane and nitrogen oxides have less impact. The impact of a gas depends on its ability to absorb long wave radiation as well as on its concentration in the atmosphere. The warmed Earth emits longer wavelength radiation (heat). Longer wave radiation is absorbed by greenhouse gases that retain the heat in the atmosphere. Global temperatures and climate patterns are influenced by concentrations of greenhouse gases. There is a correlation between rising atmospheric concentrations of carbon dioxide since the start of the industrial revolution 200 years ago and average global temperatures. Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter. Topic 5: Evolution and Biodiversity- 12 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Evidence for evolution 5.1 Evolution occurs when heritable characteristics of a species change. The fossil record provides evidence for evolution. Selective breeding of domesticated animals shows that artificial selection can cause evolution. Evolution of homologous structures by adaptive radiation explains similarities in structure when there are differences in function. Populations of a species can gradually diverge into separate species by evolution. Continuous variation across the geographical range of related populations matches the concept of gradual divergence. Natural selection 5.2 Natural selection can only occur if there is variation among members of the same species. Mutation, meiosis and sexual reproduction cause variation between individuals in a species. Adaptations are characteristics that make an individual suited to its environment and way of life. Species tend to produce more offspring than the environment can support. Individuals that are better adapted tend to survive and produce more offspring while the less well adapted tend to die or produce fewer offspring. Individuals that reproduce pass on characteristics to their offspring. Natural selection increases the frequency of characteristics that make individuals better adapted and decreases the frequency of other characteristics leading to changes within the species. Classification of biodiversity 5.3 The binomial system of names for species is universal among biologists and has been agreed and developed at a series of congresses. When species are discovered they are given scientific names using the binomial system. Taxonomists classify species using a hierarchy of taxa. All organisms are classified into three domains. The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species. In a natural classification, the genus and accompanying higher taxa consist of all the species that have evolved from one common ancestral species. Taxonomists sometimes reclassify groups of species when new evidence shows that a previous taxon contains species that have evolved from different ancestral species. Natural classifications help in identification of species and allow the prediction of characteristics shared by species within a group. Cladistics 5.4 A clade is a group of organisms that have evolved from a common ancestor. Evidence for which species are part of a clade can be obtained from the base sequences of a gene or the corresponding amino acid sequence of a protein. Sequence differences accumulate gradually so there is a positive correlation between the number of differences between two species and the time since they diverged from a common ancestor. Traits can be analogous or homologous. Cladograms are tree diagrams that show the most probable sequence of divergence in clades. Evidence from cladistics has shown that classifications of some groups based on structure did not correspond with the evolutionary origins of a group or species. Topic 6: Human Physiology- 20 Hours for Both SL and HL Subtopic Subtopic Number IB Points to Understand Digestion and absorption 6.1 The contraction of circular and longitudinal muscle of the small intestine mixes the food with enzymes and moves it along the gut. The pancreas secretes enzymes into the lumen of the small intestine. Enzymes digest most macromolecules in food into monomers in the small intestine. Villi increase the surface area of epithelium over which absorption is carried out. Villi absorb monomers formed by digestion as well as mineral ions and vitamins. Different methods of membrane transport are required to absorb different nutrients. The blood system 6.2 Arteries convey blood at high pressure from the ventricles to the tissues of the body. Arteries have muscle cells and elastic fibres in their walls. The muscle and elastic fibres assist in maintaining blood pressure between pump cycles. Blood flows through tissues in capillaries. Capillaries have permeable walls that allow exchange of materials between cells in the tissue and the blood in the capillary. Veins collect blood at low pressure from the tissues of the body and return it to the atria of the heart. Valves in veins and the heart ensure circulation of blood by preventing backflow. There is a separate circulation for the lungs. The heart beat is initiated by a group of specialized muscle cells in the right atrium called the sinoatrial node. The sinoatrial node acts as a pacemaker. The sinoatrial node sends out an electrical signal that stimulates contraction as it is propagated through the walls of the atria and then the walls of the ventricles. The heart rate can be increased or decreased by impulses brought to the heart through two nerves from the medulla of the brain. Epinephrine increases the heart rate to prepare for vigorous physical activity. Defense against infectious disease 6.3 The skin and mucous membranes form a primary defense against pathogens that cause infectious disease. Cuts in the skin are sealed by blood clotting. Clotting factors are released from platelets. The cascade results in the rapid conversion of fibrinogen to fibrin by thrombin. Ingestion of pathogens by phagocytic white blood cells gives non-specific immunity to diseases. Production of antibodies by lymphocytes in response to particular pathogens gives specific immunity. Antibiotics block processes that occur in prokaryotic cells but not in eukaryotic cells. Viruses lack a metabolism and cannot therefore be treated with antibiotics. Some strains of bacteria have evolved with genes that confer resistance to antibiotics and some strains of bacteria have multiple resistance. Gas exchange 6.4 Ventilation maintains concentration gradients of oxygen and carbon dioxide between air in alveoli and blood flowing in adjacent capillaries. Type I pneumocytes are extremely thin alveolar cells that are adapted to carry out gas exchange. Type II pneumocytes secrete a solution containing surfactant that creates a moist surface inside the alveoli to prevent the sides of the alveolus adhering to each other by reducing surface tension. Air is carried to the lungs in the trachea and bronchi and then to the alveoli in bronchioles. Muscle contractions cause the pressure changes inside the thorax that force air in and out of the lungs to ventilate them. Different muscles are required for inspiration and expiration because muscles only do work when they contract. Neurons and synapses 6.5 Neurons transmit electrical impulses. The myelination of nerve fibres allows for saltatory conduction. Neurons pump sodium and potassium ions across their membranes to generate a resting potential. An action potential consists of depolarization and repolarization of the neuron. Nerve impulses are action potentials propagated along the axons of neurons. Propagation of nerve impulses is the result of local currents that cause each successive part of the axon to reach the threshold potential. Synapses are junctions between neurons and between neurons and receptor or effector cells. When presynaptic neurons are depolarized they release a neurotransmitter into the synapse. A nerve impulse is only initiated if the threshold potential is reached. Hormones, homeostasis and reproduction 6.6 Insulin and glucagon are secreted by ÃŽ ² and ÃŽ ± cells of the pancreas respectively to control blood glucose concentration. Thyroxin is secreted by the thyroid gland to regulate the metabolic rate and help control body temperature. Leptin is secreted by cells in adipose tissue and acts on the hypothalamus of the brain to inhibit appetite. Melatonin is secreted by the pineal gland to control circadian rhythms. A gene on the Y chromosome causes embryonic gonads to develop as testes and secrete testosterone. Testosterone causes pre-natal development of male genitalia and both sperm production and development of male secondary sexual characteristics during puberty. Estrogen and progesterone cause pre-natal development of female reproductive organs and female secondary sexual characteristics during puberty. The menstrual cycle is controlled by negative and positive feedback mechanisms involving ovarian and pituitary hormones. Additional Higher Level Topics Only students taking IB Biology HL cover these topics. They consist of 60 hours of study. Topic 7: Nucleic Acids- 9 Hours for HL Only Subtopic Subtopic Number IB Points to Understand DNA structure and replication (HL ONLY) 7.1 Nucleosomes help to supercoil the DNA. DNA structure suggested a mechanism for DNA replication. DNA polymerases can only add nucleotides to the 3’ end of a primer. DNA replication is continuous on the leading strand and discontinuous on the lagging strand. DNA replication is carried out by a complex system of enzymes. Some regions of DNA do not code for proteins but have other important functions. Transcription and gene expression (HL ONLY) 7.2 Transcription occurs in a 5’ to 3’ direction. Nucleosomes help to regulate transcription in eukaryotes. Eukaryotic cells modify mRNA after transcription. Splicing of mRNA increases the number of different proteins an organism can produce. Gene expression is regulated by proteins that bind to specific base sequences in DNA. The environment of a cell and of an organism has an impact on gene expression. Translation (HL ONLY) 7.3 Initiation of translation involves assembly of the components that carry out the process. Synthesis of the polypeptide involves a repeated cycle of events. Disassembly of the components follows termination of translation. Free ribosomes synthesize proteins for use primarily within the cell. Bound ribosomes synthesize proteins primarily for secretion or for use in lysosomes. Translation can occur immediately after transcription in prokaryotes due to the absence of a nuclear membrane. The sequence and number of amino acids in the polypeptide is the primary structure. The secondary structure is the formation of alpha helices and beta pleated sheets stabilized by hydrogen bonding. The tertiary structure is the further folding of the polypeptide stabilized by interactions between R groups. The quaternary structure exists in proteins with more than one polypeptide chain. Want to get better grades and test scores? We can help. PrepScholar Tutors is the world's best tutoring service. We combine world-class expert tutors with our proprietary teaching techniques. Our students have gotten A's on thousands of classes, perfect 5's on AP tests, and ludicrously high SAT Subject Test scores. Whether you need help with science, math, English, social science, or more, we've got you covered. Get better grades today with PrepScholar Tutors. Topic 8: Metabolism, Cell Respiration, and Photosynthesis- 14 Hours for HL Only Subtopic Subtopic Number IB Points to Understand Metabolism (HL ONLY) 8.1 Metabolic pathways consist of chains and cycles of enzyme-catalysed reactions. Enzymes lower the activation energy of the chemical reactions that they catalyse. Enzyme inhibitors can be competitive or non-competitive. Metabolic pathways can be controlled by end-product inhibition. Cell respiration (HL ONLY) 8.2 Cell respiration involves the oxidation and reduction of electron carriers. Phosphorylation of molecules makes them less stable. In glycolysis, glucose is converted to pyruvate in the cytoplasm. Glycolysis gives a small net gain of ATP without the use of oxygen. In aerobic cell respiration pyruvate is decarboxylated and oxidized, and converted into acetyl compound and attached to coenzyme A to form acetyl coenzyme A in the link reaction. In the Krebs cycle, the oxidation of acetyl groups is coupled to the reduction of hydrogen carriers, liberating carbon dioxide. Energy released by oxidation reactions is carried to the cristae of the mitochondria by reduced NAD and FAD. Transfer of electrons between carriers in the electron transport chain in the membrane of the cristae is coupled to proton pumping. In chemiosmosis protons diffuse through ATP synthase to generate ATP. Oxygen is needed to bind with the free protons to maintain the hydrogen gradient, resulting in the formation of water. The structure of the mitochondrion is adapted to the function it performs. Photosynthesis (HL ONLY) 8.3 Light-dependent reactions take place in the intermembrane space of the thylakoids. Light-independent reactions take place in the stroma. Reduced NADP and ATP are produced in the light-dependent reactions. Absorption of light by photosystems generates excited electrons. Photolysis of water generates electrons for use in the light-dependent reactions. Transfer of excited electrons occurs between carriers in thylakoid membranes. Excited electrons from Photosystem II are used to contribute to generate a proton gradient. ATP synthase in thylakoids generates ATP using the proton gradient. Excited electrons from Photosystem I are used to reduce NADP. In the light-independent reactions a carboxylase catalyses the carboxylation of ribulose bisphosphate. Glycerate 3-phosphate is reduced to triose phosphate using reduced NADP and ATP. Triose phosphate is used to regenerate RuBP and produce carbohydrates. Ribulose bisphosphate is reformed using ATP. The structure of the chloroplast is adapted to its function in photosynthesis. Topic 9: Plant Biology- 13 Hours for HL Only Subtopic Subtopic Number IB Points to Understand Transport in the xylem of plants (HL ONLY) 9.1 Transpiration is the inevitable consequence of gas exchange in the leaf. Plants transport water from the roots to the leaves to replace losses from transpiration. The cohesive property of water and the structure of the xylem vessels allow transport under tension. The adhesive property of water and evaporation generate tension forces in leaf cell walls. Active uptake of mineral ions in the roots causes absorption of water by osmosis. Transport in the phloem of plants (HL ONLY) 9.2 Plants transport organic compounds from sources to sinks. Incompressibility of water allows transport along hydrostatic pressure gradients. Active transport is used to load organic compounds into phloem sieve tubes at the source. High concentrations of solutes in the phloem at the source lead to water uptake by osmosis. Raised hydrostatic pressure causes the contents of the phloem to flow towards sinks. Growth in plants (HL ONLY) 9.3 Undifferentiated cells in the meristems of plants allow indeterminate growth. Mitosis and cell division in the shoot apex provide cells needed for extension of the stem and development of leaves. Plant hormones control growth in the shoot apex. Plant shoots respond to the environment by tropisms. Auxin efflux pumps can set up concentration gradients of auxin in plant tissue. Auxin influences cell growth rates by changing the pattern of gene expression. Reproduction in plants (HL ONLY) 9.4 Flowering involves a change in gene expression in the shoot apex. The switch to flowering is a response to the length of light and dark periods in many plants. Success in plant reproduction depends on pollination, fertilization and seed dispersal. Most flowering plants use mutualistic relationships with pollinators in sexual reproduction. Topic #10: Genetics and Evolution- 8 Hours for HL Only Subtopic Subtopic Number IB Points to Understand Meiosis (HL ONLY) 10.1 Chromosomes replicate in interphase before meiosis. Crossing over is the exchange of DNA material between non-sister homologous chromatids. Crossing over produces new combinations of alleles on the chromosomes of the haploid cells. Chiasmata formation between non-sister chromatids can result in an exchange of alleles. Homologous chromosomes separate in meiosis I. Sister chromatids separate in meiosis II. Independent assortment of genes is due to the random orientation of pairs of homologous chromosomes in meiosis I. Inheritance (HL ONLY) 10.2 Gene loci are said to be linked if on the same chromosome. Unlinked genes segregate independently as a result of meiosis. Variation can be discrete or continuous. The phenotypes of polygenic characteristics tend to show continuous variation. Chi-squared tests are used to determine whether the difference between an observed and expected frequency distribution is statistically significant. Gene pools and speciation (HL ONLY) 10.3 A gene pool consists of all the genes and their different alleles, present in an interbreeding population. Evolution requires that allele frequencies change with time in populations. Reproductive isolation of populations can be temporal, behavioural or geographic. Speciation due to divergence of isolated populations can be gradual. Speciation can occur abruptly. Topic 11: Animal Physiology- 16 Hours for HL Only Subtopic Subtopic Number IB Points to Understand Antibody production and vaccination (HL ONLY) 11.1 Every organism has unique molecules on the surface of its cells. Pathogens can be species-specific although others can cross species barriers. B lymphocytes are activated by T lymphocytes in mammals. Activated B cells multiply to form clones of plasma cells and memory cells. Plasma cells secrete antibodies. Antibodies aid the destruction of pathogens. White cells release histamine in response to allergens. Histamines cause allergic symptoms. Immunity depends upon the persistence of memory cells. Vaccines contain antigens that trigger immunity but do not cause the disease. Fusion of a tumour cell with an antibody-producing plasma cell creates a hybridoma cell. Monoclonal antibodies are produced by hybridoma cells. Movement (HL ONLY) 11.2 Bones and exoskeletons provide anchorage for muscles and act as levers. Synovial joints allow certain movements but not others. Movement of the body requires muscles to work in antagonistic pairs. Skeletal muscle fibres are multinucleate and contain specialized endoplasmic reticulum. Muscle fibres contain many myofibrils. Each myofibril is made up of contractile sarcomeres. The contraction of the skeletal muscle is achieved by the sliding of actin and myosin filaments. ATP hydrolysis and cross bridge formation are necessary for the filaments to slide. Calcium ions and the proteins tropomyosin and troponin control muscle contractions. The kidney and osmoregulation (HL ONLY) 11.3 Animals are either osmoregulators or osmoconformers. The Malpighian tubule system in insects and the kidney carry out osmoregulation and removal of nitrogenous wastes. The composition of blood in the renal artery is different from that in the renal vein. The ultrastructure of the glomerulus and Bowman’s capsule facilitate ultrafiltration. The proximal convoluted tubule selectively reabsorbs useful substances by active transport. The loop of Henle maintains hypertonic conditions in the medulla. ADH controls reabsorption of water in the collecting duct. The length of the loop of Henle is positively correlated with the need for water conservation in animals. The type of nitrogenous waste in animals is correlated with evolutionary history and habitat. Sexual reproduction (HL ONLY) 11.4 Spermatogenesis and oogenesis both involve mitosis, cell growth, two divisions of meiosis and differentiation. Processes in spermatogenesis and oogenesis result in different numbers of gametes with different amounts of cytoplasm. Fertilization in animals can be internal or external. Fertilization involves mechanisms that prevent polyspermy. Implantation of the blastocyst in the endometrium is essential for the continuation of pregnancy. HCG stimulates the ovary to secrete progesterone during early pregnancy. The placenta facilitates the exchange of materials between the mother and fetus. Estrogen and progesterone are secreted by the placenta once it has formed. Birth is mediated by positive feedback involving estrogen and oxytocin. Options As a part of the IB Biology class, you'll cover one additional subject from the options below. (Typically you don’t choose, but rather your teacher does.) Whichever option you or your teacher chooses, you'll cover three or four topics (15 hours total) for SL and an additional two or three topics (25 hours total) for HL. Option A: Neurobiology and Behaviour- 15 Hours for SL and 25 hours for HL Subtopic Subtopic Number IB Points to Understand Neural development A.1 The neural tube of embryonic chordates is formed by infolding of ectoderm followed by elongation of the tube. Neurons are initially produced by differentiation in the neural tube. Immature neurons migrate to a final location. An axon grows from each immature neuron in response to chemical stimuli. Some axons extend beyond the neural tube to reach other parts of the body. A developing neuron forms multiple synapses. Synapses that are not used do not persist. Neural pruning involves the loss of unused neurons. The plasticity of the nervous system allows it to change with experience. The human brain A.2 The anterior part of the neural tube expands to form the brain. Different parts of the brain have specific roles. The autonomic nervous system controls involuntary processes in the body using centres located mainly in the brain stem. The cerebral cortex forms a larger proportion of the brain and is more highly developed in humans than other animals. The human cerebral cortex has become enlarged principally by an increase in total area with extensive folding to accommodate it within the cranium. The cerebral hemispheres are responsible for higher order functions. The left cerebral hemisphere receives sensory input from sensory receptors in the right side of the body and the right side of the visual field in both eyes and vice versa for the right hemisphere. The left cerebral hemisphere controls muscle contraction in the right side of the body and vice versa for the right hemisphere. Brain metabolism requires large energy inputs. Perception of stimuli A.3 Receptors detect changes in the environment. Rods and cones are photoreceptors located in the retina. Rods and cones differ in their sensitivities to light intensities and wavelengths. Bipolar cells send the impulses from rods and cones to ganglion cells. Ganglion cells send messages to the brain via the optic nerve. The information from the right field of vision from both eyes is sent to the left part of the visual cortex and vice versa. Structures in the middle ear transmit and amplify sound. Sensory hairs of the cochlea detect sounds of specific wavelengths. Impulses caused by sound perception are transmitted to the brain via the auditory nerve. Hair cells in the semicircular canals detect movement of the head. Additional HL Neurobiology and Behaviour Topics- 10 More Hours for HL Innate and learned behaviour (HL ONLY) A.4 Innate behaviour is inherited from parents and so develops independently of the environment. Autonomic and involuntary responses are referred to as reflexes. Reflex arcs comprise the neurons that mediate reflexes. Reflex conditioning involves forming new associations. Learned behaviour develops as a result of experience. Imprinting is learning occurring at a particular life stage and is independent of the consequences of behaviour. Operant conditioning is a form of learning that consists of trial and error experiences. Learning is the acquisition of skill or knowledge. Memory is the process of encoding, storing and accessing information. Neuropharmacology (HL ONLY) A.5 Some neurotransmitters excite nerve impulses in postsynaptic neurons and others inhibit them. Nerve impulses are initiated or inhibited in post-synaptic neurons as a result of summation of all excitatory and inhibitory neurotransmitters received from presynaptic neurones. Many different slow-acting neurotransmitters modulate fast synaptic transmission in the brain. Memory and learning involve changes in neurones caused by slow-acting neurotransmitters. Psychoactive drugs affect the brain by either increasing or decreasing postsynaptic transmission. Anesthetics act by interfering with neural transmission between areas of sensory perception and the CNS. Stimulant drugs mimic the stimulation provided by the sympathetic nervous system. Addiction can be affected by genetic predisposition, social environment and dopamine secretion. Ethology (HL ONLY) A.6 Ethology is the study of animal behaviour in natural conditions. Natural selection can change the frequency of observed animal behaviour. Behaviour that increases the chances of survival and reproduction will become more prevalent in a population. Learned behaviour can spread through a population or be lost from it more rapidly than innate behaviour. Option B: Biotechnology and Bioinformatics- 15 Hours for SL and HL Subtopic Subtopic Number IB Points to Understand Microbiology: organisms in industry B.1 Microorganisms are metabolically diverse. Microorganisms are used in industry because they are small and have a fast growth rate. Pathway engineering optimizes genetic and regulatory processes within microorganisms. Pathway engineering is used industrially to produce metabolites of interest. Fermenters allow large-scale production of metabolites by microorganisms. Fermentation is carried out by batch or continuous culture. Microorganisms in fermenters become limited by their own waste products. Probes are used to monitor conditions within fermenters. Conditions are maintained at optimal levels for the growth of the microorganisms being cultured. Biotechnology in agriculture B.2 Transgenic organisms produce proteins that were not previously part of their species’ proteome. Genetic modification can be used to overcome environmental resistance to increase crop yields. Genetically modified crop plants can be used to produce novel products. Bioinformatics plays a role in identifying target genes. The target gene is linked to other sequences that control its expression. An open reading frame is a significant length of DNA from a start codon to a stop codon. Marker genes are used to indicate successful uptake. Recombinant DNA must be inserted into the plant cell and taken up by its chromosome or chloroplast DNA. Recombinant DNA can be introduced into whole plants, leaf discs or protoplasts. Recombinant DNA can be introduced by direct physical and chemical methods or indirectly by vectors. Environmental protection B.3 Responses to pollution incidents can involve bioremediation combined with physical and chemical procedures. Microorganisms are used in bioremediation. Some pollutants are metabolized by microorganisms. Cooperative aggregates of microorganisms can form biofilms. Biofilms possess emergent properties. Microorganisms growing in a biofilm are highly resistant to antimicrobial agents. Microorganisms in biofilms cooperate through quorum sensing. Bacteriophages are used in the disinfection of water systems. Additional HL Biotechnology and Bioinfomatics Topics- 10 More Hours for HL Medicine (HL ONLY) B.4 Infection by a pathogen can be detected by the presence of its genetic material or by its antigens. Predisposition to a genetic disease can be detected through the presence of markers. DNA microarrays can be used to test for genetic predisposition or to diagnose the disease. Metabolites that indicate disease can be detected in blood and urine. Tracking experiments are used to gain information about the localization and interaction of a desired protein. Biopharming uses genetically modified animals and plants to produce proteins for therapeutic use. Viral vectors can be used in gene therapy. Bioinformatics (HL ONLY) B.5 Databases allow scientists easy access to information. The body of data stored in databases is increasing exponentially. BLAST searches can identify similar sequences in different organisms. Gene function can be studied using model organisms with similar sequences. Sequence alignment software allows comparison of sequences from different organisms. BLASTn allows nucleotide sequence alignment while BLASTp allows protein alignment. Databases can be searched to compare newly identified sequences with sequences of known function in other organisms. Multiple sequence alignment is used in the study of phylogenetics. EST is an expressed sequence tag that can be used to identify potential genes. Option C: Ecology and Conservation- 15 Hours for SL and HL Subtopic Subtopic Number IB Points to Understand Species and communities C.1 The distribution of species is affected by limiting factors. Community structure can be strongly affected by keystone species. Each species plays a unique role within a community because of the unique combination of its spatial habitat and interactions with other species. Interactions between species in a community can be classified according to their effect. Two species cannot survive indefinitely in the same habitat if their niches are identical. Communities and ecosystems C.2 Most species occupy different trophic levels in multiple food chains. A food web shows all the possible food chains in a community. The percentage of ingested energy converted to biomass is dependent on the respiration rate. The type of stable ecosystem that will emerge in an area is predictable based on climate. In closed ecosystems energy but not matter is exchanged with the surroundings. Disturbance influences the structure and rate of change within ecosystems. Impacts of humans on ecosystems C.3 Introduced alien species can escape into local ecosystems and become invasive. Competitive exclusion and the absence of predators can lead to reduction in the numbers of endemic species when alien species become invasive. Pollutants become concentrated in the tissues of organisms at higher trophic levels by biomagnification. Macroplastic and microplastic debris has accumulated in marine environments. Conservation of biodiversity C.4 An indicator species is an organism used to assess a specific environmental condition. Relative numbers of indicator species can be used to calculate the value of a biotic index. In situ conservation may require active management of nature reserves or national parks. Ex situ conservation is the preservation of species outside their natural habitats. Biogeographic factors affect species diversity. Richness and evenness are components of biodiversity. Additional HL Ecology and Conservation Topics- 10 More Hours for HL Population ecology (HL ONLY) C.5 Sampling techniques are used to estimate population size. The exponential growth pattern occurs in an ideal, unlimited environment. Population growth slows as a population reaches the carrying capacity of the environment. The phases shown in the sigmoid curve can be explained by relative rates of natality, mortality, immigration and emigration. Limiting factors can be top down or bottom up. Nitrogen and phosphorus cycles (HL ONLY) C.6 Nitrogen-fixing bacteria convert atmospheric nitrogen to ammonia. Rhizobium associates with roots in a mutualistic relationship. In the absence of oxygen denitrifying bacteria reduce nitrate in the soil. Phosphorus can be added to the phosphorus cycle by application of fertilizer or removed by the harvesting of agricultural crops. The rate of turnover in the phosphorus cycle is much lower than the nitrogen cycle. Availability of phosphate may become limiting to agriculture in the future. Leaching of mineral nutrients from agricultural land into rivers causes eutrophication and leads to increased biochemical oxygen demand. Option D: Human Physiology- 15 Hours for SL and HL Subtopic Subtopic Number IB Points to Understand Human nutrition D.1 Essential nutrients cannot be synthesized by the body, therefore they have to be included in the diet. Dietary minerals are essential chemical elements. Vitamins are chemically diverse carbon compounds that cannot be synthesized by the body. Some fatty acids and some amino acids are essential. Lack of essential amino acids affects the production of proteins. Malnutrition may be caused by a deficiency, imbalance or excess of nutrients in the diet. Appetite is controlled by a centre in the hypothalamus. Overweight individuals are more likely to suffer hypertension and type II diabetes. Starvation can lead to breakdown of body tissue. Digestion D.2 Nervous and hormonal mechanisms control the secretion of digestive juices. Exocrine glands secrete to the surface of the body or the lumen of the gut. The volume and content of gastric secretions are controlled by nervous and hormonal mechanisms. Acid conditions in the stomach favour some hydrolysis reactions and help to control pathogens in ingested food. The structure of cells of the epithelium of the villi is adapted to the absorption of food. The rate of transit of materials through the large intestine is positively correlated with their fibre content. Materials not absorbed are egested. Functions of the liver D.3 The liver removes toxins from the blood and detoxifies them. Components of red blood cells are recycled by the liver. The breakdown of erythrocytes starts with phagocytosis of red blood cells by Kupffer cells. Iron is carried to the bone marrow to produce hemoglobin in new red blood cells. Surplus cholesterol is converted to bile salts. Endoplasmic reticulum and Golgi apparatus in hepatocytes produce plasma proteins. The liver intercepts blood from the gut to regulate nutrient levels. Some nutrients in excess can be stored in the liver. The heart D.4 Structure of cardiac muscle cells allows propagation of stimuli through the heart wall. Signals from the sinoatrial node that cause contraction cannot pass directly from atria to ventricles. There is a delay between the arrival and passing on of a stimulus at the atrioventricular node. This delay allows time for atrial systole before the atrioventricular valves close. Conducting fibres ensure coordinated contraction of the entire ventricle wall. Normal heart sounds are caused by the atrioventricular valves and semilunar valves closing causing changes in blood flow. Additional HL Human Physiology Topics- 10 More Hours for HL Hormones and metabolism (HL ONLY) D.5 Endocrine glands secrete hormones directly into the bloodstream. Steroid hormones bind to receptor proteins in the cytoplasm of the target cell to form a receptor–hormone complex. The receptor–hormone complex promotes the transcription of specific genes. Peptide hormones bind to receptors in the plasma membrane of the target cell. Binding of hormones to membrane receptors activates a cascade mediated by a second messenger inside the cell. The hypothalamus controls hormone secretion by the anterior and posterior lobes of the pituitary gland. Hormones secreted by the pituitary control growth, developmental changes, reproduction and homeostasis. Transport of respiratory gases (HL ONLY) D.6 Oxygen dissociation curves show the affinity of hemoglobin for oxygen. Carbon dioxide is carried in solution and bound to hemoglobin in the blood. Carbon dioxide is transformed in red blood cells into hydrogencarbonate ions. The Bohr shift explains the increased release of oxygen by hemoglobin in respiring tissues. Chemoreceptors are sensitive to changes in blood pH. The rate of ventilation is controlled by the respiratory control centre in the medulla oblongata. During exercise the rate of ventilation changes in response to the amount of CO2 in the blood. Fetal hemoglobin is different from adult hemoglobin allowing the transfer of oxygen in the placenta onto the fetal hemoglobin. Practical Scheme of Work You also need to complete experiments and experimental reports as a part of any IB Science course. For SL, there is 40 hours of material. For HL, there is 60 hours of material. Here are the activities: Practical activities: 20 hours for SL and 40 hours for HL Lab work in class counts towards these hours Individual investigation (internal assessment-IA): 10 hours for SL and HL A lab project along with a report that counts as 20% of your IB exam scores (written exam counts for the other 80%) Group 4 Project:10 hours for SL and HL Students are separated into groups and must conduct an experiment and write a report. Experiments may not be this cool. What’s Next? Thinking about taking AP Biology instead? Learn what's covered in a AP Bio here. Looking for more in-depth explorations of the topics mentioned on this syllabus? Read our subject-specific articles on topics varying from the photosynthesis equation to homologous and analogous structures to cell biology (including cell theory, enzymes, and how the cell membrane and endoplasmic reticulum work). Are you hoping to squeeze in some extra IB classes? Learn about the IB courses offered online. Studying for the SAT? Check out our complete guide to the SAT. Taking the SAT in the next month? Check out our guide to cramming. Not sure where you want to go to college? Check out our guide to finding your target school. Want to improve your SAT score by 160 points or your ACT score by 4 points? We've written a guide for each test about the top 5 strategies you must be using to have a shot at improving your score. Download it for free now:

A Look into Edna St. Vincent Millay’s Poem

Vincent Millay could be justified by the fact that readers can easily relate to it because it talks about a universal theme, which is love. Although it reeks of regret and loneliness, the poet effectively successfully used palpable symbols and words to describe the past events that transpired in her life. In the poem, the speaker casts herself as a â€Å"lonely tree†. One writer, Epstein (2001) proclaims that this poem is â€Å"a summing up of [the author’s] love life to date, and an occasion to invoke the classic themes of elegy, the tempus fugit and the ubi sunt† (p. 139): What lips my lips have kissed, and where, and why I have forgotten, and what arms have lain Under my head till morning . . . . . . . . . . . . . . . . . . . . . . And in my heart there stirs a quiet pain For unremembered lads that not again Will turn to me at midnight with a cry. Thus in the winter stands the lonely tree, Nor knows what birds have vanished one by one, Yet knows its boughs more silent than before. It seems that the speaker in the poem is an aging lady signified by the songless tree. Indeed, she is an epitome of loneliness and regret, one that we might be tempted to read as a prototype of abandoned womanhood, pathetic and powerless. Male desire in the love sonnets where the woman as a speaker always masquerades feminine weakness and sentimentality; often beseeching, and consumed by desire. However, when a male lover speaks, it would imply â€Å"authority of suffering and, perhaps more importantly, with the authority of convention†. When Millay masquerades as a male poet masquerading as a lovesick woman, the â€Å"sense of where sincerity meets gesture and how authority aligns itself with gender is confused† (Freedman, 1995, p. 113). In its structure, the poem is classified as a sonnet that has a particular rhyming pattern: abbaabba cdedce. The poem uses alliteration and assonance. It is also rich in naturally-occurring symbols, which all readers can easily connect. The poem begins with a one-sentence octave that presents the situation in which the narrator finds herself–inside a house during the rain, reminiscing about her past and forgotten lovers. The inverted sentence structure of the first two lines almost suggests a question rather than a statement: How many lovers were there? The alliterations in the first line additionally emphasize the repetitiveness of the narrator’s sexual encounters. At the same time, the perfect tense mean that this phase of her life has been completed, and the body part symbolisms of lips, arms, and head imply her distance from the experience. In the third line, Millay moves to the present tense, where she describes the memories of her lovers (using a ghost metaphor) aroused by the rain, a symbol for gloom and melancholia. These are the lovers that â€Å"tap and sigh†. The narrator seems insinuating that the lovers themselves are irrelevant. For the same reason, â€Å"Millay picks a metaphor that hints at facelessness and lack of welcome and resonates with the specific time of the midnight hour†. The central phrase in this section is â€Å"quiet pain,† an â€Å"almost-oxymoron suggesting that the narrator’s grief is muted or accepted† (Schurer, 2005). As signified by the forward movement of tenses, Millay gives the readers a slight glimpse of things to come as well: However, undeniably, she   regrets everything and she expects no intimacy in the future. In the end, the female narrator seems not interested in the identity of her lovers as in the memory of the emotions they allowed her to experience.   Despite the sadness and regret, the narrator presented peace or redemption as a â€Å"faint echo of the emotion of love from her youth† (Schurer, 2005). Despite the lonely themes and symbols, we can sense of equality in love; to the demand by women that they be allowed to enter the world of adventure and experiment in love which men have long inhabited. However, Millay does not sound to be any feminist to argue for that equality. She just makes it subtle, exhibits it in this poem and turns it into beauty. Works Cited Epstein, Daniel Mark. What Lips My Lips Have Kissed: The Loves and Love Poems of Edna St. Vincent Millay. New York: Holt, 2001. Freedman, Diane P., ed. Millay at 100: A Critical Reappraisal. Carbondale, IL: Southern Illinois University Press, 1995. Schurer, Norbert. â€Å"Millay’s what lips my lips have kissed, and where, and why†, The Explicator, 63.2 (Winter 2005): 94-97. A Look into Edna St. Vincent Millay’s Poem Vincent Millay could be justified by the fact that readers can easily relate to it because it talks about a universal theme, which is love. Although it reeks of regret and loneliness, the poet effectively successfully used palpable symbols and words to describe the past events that transpired in her life. In the poem, the speaker casts herself as a â€Å"lonely tree†. One writer, Epstein (2001) proclaims that this poem is â€Å"a summing up of [the author’s] love life to date, and an occasion to invoke the classic themes of elegy, the tempus fugit and the ubi sunt† (p. 139): What lips my lips have kissed, and where, and why I have forgotten, and what arms have lain Under my head till morning . . . . . . . . . . . . . . . . . . . . . . And in my heart there stirs a quiet pain For unremembered lads that not again Will turn to me at midnight with a cry. Thus in the winter stands the lonely tree, Nor knows what birds have vanished one by one, Yet knows its boughs more silent than before. It seems that the speaker in the poem is an aging lady signified by the songless tree. Indeed, she is an epitome of loneliness and regret, one that we might be tempted to read as a prototype of abandoned womanhood, pathetic and powerless. Male desire in the love sonnets where the woman as a speaker always masquerades feminine weakness and sentimentality; often beseeching, and consumed by desire. However, when a male lover speaks, it would imply â€Å"authority of suffering and, perhaps more importantly, with the authority of convention†. When Millay masquerades as a male poet masquerading as a lovesick woman, the â€Å"sense of where sincerity meets gesture and how authority aligns itself with gender is confused† (Freedman, 1995, p. 113). In its structure, the poem is classified as a sonnet that has a particular rhyming pattern: abbaabba cdedce. The poem uses alliteration and assonance. It is also rich in naturally-occurring symbols, which all readers can easily connect. The poem begins with a one-sentence octave that presents the situation in which the narrator finds herself–inside a house during the rain, reminiscing about her past and forgotten lovers. The inverted sentence structure of the first two lines almost suggests a question rather than a statement: How many lovers were there? The alliterations in the first line additionally emphasize the repetitiveness of the narrator’s sexual encounters. At the same time, the perfect tense mean that this phase of her life has been completed, and the body part symbolisms of lips, arms, and head imply her distance from the experience. In the third line, Millay moves to the present tense, where she describes the memories of her lovers (using a ghost metaphor) aroused by the rain, a symbol for gloom and melancholia. These are the lovers that â€Å"tap and sigh†. The narrator seems insinuating that the lovers themselves are irrelevant. For the same reason, â€Å"Millay picks a metaphor that hints at facelessness and lack of welcome and resonates with the specific time of the midnight hour†. The central phrase in this section is â€Å"quiet pain,† an â€Å"almost-oxymoron suggesting that the narrator’s grief is muted or accepted† (Schurer, 2005). As signified by the forward movement of tenses, Millay gives the readers a slight glimpse of things to come as well: However, undeniably, she   regrets everything and she expects no intimacy in the future. In the end, the female narrator seems not interested in the identity of her lovers as in the memory of the emotions they allowed her to experience.   Despite the sadness and regret, the narrator presented peace or redemption as a â€Å"faint echo of the emotion of love from her youth† (Schurer, 2005). Despite the lonely themes and symbols, we can sense of equality in love; to the demand by women that they be allowed to enter the world of adventure and experiment in love which men have long inhabited. However, Millay does not sound to be any feminist to argue for that equality. She just makes it subtle, exhibits it in this poem and turns it into beauty. Works Cited Epstein, Daniel Mark. What Lips My Lips Have Kissed: The Loves and Love Poems of Edna St. Vincent Millay. New York: Holt, 2001. Freedman, Diane P., ed. Millay at 100: A Critical Reappraisal. Carbondale, IL: Southern Illinois University Press, 1995. Schurer, Norbert. â€Å"Millay’s what lips my lips have kissed, and where, and why†, The Explicator, 63.2 (Winter 2005): 94-97.

What were the significant issues of American foreign policy under Essay

What were the significant issues of American foreign policy under President Theodore Roosevelt Explain - Essay Example This policy of non-intervention continued until the end of the nineteenth century, when a call for America to pursue a more proactive role in world affairs, in keeping with her position as a great power, began to gain popularity. Its chief adherents were in the Republican Party, and consisted of Theodore Roosevelt, Admiral Alfred Mahan, John Hay and Senator Henry Cabot Lodge, who advocated America’s adoption of â€Å"the large policy† committed to the expansion of U.S. influence and territory overseas (Raico, 1995). President Theodore Roosevelt may be considered the chief architect of America’s new foreign policy of active intervention in global affairs. Theodore Roosevelt was born on 27 October, 1858, in New York City. He graduated from Harvard and went on to study Law at Columbia University, dropping out in pursuit of interest in politics, and winning a seat in the New York Assembly in 1882. He subsequently served as Civil Service Commissioner, President of the New York City Police Board and Assistant Secretary of the Navy. As the commandant of the ‘Rough Riders’ regiment, he was a hero in the Spanish-American War. He became the Governor of New York State in 1898 and then the Vice-President under President McKinley in 1900. On McKinley’s assassination in 1901, Theodore Roosevelt became the President of the United States and remained in that office until 1909. Roosevelt extended the influence and stature of the executive, introduced conservation and progressive reforms through welfare measures, government regulation of big business and his ‘Square Deal’ approach to domestic economy and social justic e. Roosevelt died on 6 January, 1919. (Miller Center of Public Affairs website). President Theodore Roosevelt embarked on an aggressive foreign policy geared to make America the most influential force in global affairs. In keeping with his diplomatic motto to â€Å"speak softly

Human Resources Management Essay Example | Topics and Well Written Essays - 2250 words

Human Resources Management - Essay Example REFERENCES EXECUTIVE SUMMARY The role of human resources manager is very diverse and requires a complicated individual in the job role with a vast understanding of information technology, human behaviour knowledge, psychology, conflict resolution, and planning innovator. HRM now fulfils, due to environmental or internal factors, a role where more intervention and inter-connectivity between line management roles and strategic leadership are becoming strengthened. It is not a segregated business function today where once it was likely limited to just control methodologies to secure lower budgeting; a hard view of HRM. It is much softer today and requires empowerment strategies as a key resource for improving the competitive position of the business or bring more human-related value. This report identifies the changing role of HRM using appropriate expert theory and experience. Introduction The role of human resources managers has changed in recent years, most of which is derived of cha nging roles and activities within the entire business network. Areas such as supply chain, global competition, new technology development and attitude recognition of workers at the psychological level in order to gain new motivation or performance outcomes have brought these changes. There is must more interaction between human resources and line management as a product of these evolutions, therefore seeming to make them indistinguishable and also inter-connected roles. From recruitment through the process of ensuring employees achieve a satisfactory work environment when measured against performance standards, the HRM process is that of a counsellor, coach, mentor, skills developer, and even strategist. There is virtually no area of the business that is not, in some fashion, influenced by the HR manager or the processes that guide HR practices. The roles of HRM Empowerment of workers is one of the major human resource goals and is a central focus of their activities. â€Å"Empower ment will allow greater control over non-management staff by line managers and supervisors when given authority or more authority in areas such as recruitment, discipline and absence control† (Yusoff & Abdullah, 2008, p.10). Thus, there is a control element of the HRM role when working toward some sort of empowerment model. The HRM manager acts then as a facilitator of empowerment for not only the worker, but colleagues at the management level. They allow managers to become familiarized with and adapt to changing human resources principles and then offer them guidance to remain self-focused on running the management floor. â€Å"HR should be a support for departmental managers and members of staff. For that they should come out of their office and talk to people and not delegate the job to departmental managers† (Watson, Maxwell & Farquharson, 2007, p.31). This author reinforces that the role of HR is highly visible in the organization and there is direct contact with s enior-level managers or same-level management peers only as a facilitator of their line management activities with a touch of human resources focus1. It reinforces the connection between management and operations and the HR practitioner in a way that provides stronger connections with managers and meets the overall goal of empowering them to take HR action where needed; and perhaps recognise where certain deficiencies lie. The HR manager also works with a composite of different technologies to support the HR function. Computer

The Law on Recovery for Psychiatric Injury Caused by Negligence is Essay

The Law on Recovery for Psychiatric Injury Caused by Negligence is Strongly in Need of Reform - Essay Example This is because there must be actual psychiatric injury that is easy to prove which makes sorrow, grief and fear not sufficient to win a case. For a defendant to be established as negligent, the claimant must be able to prove three things.2 First aspect, the claimant must prove that the defendant owed the claimant a duty of care which is a responsibility to avoid sloppy actions that could cause damage to one or more persons. The duty of care is further explained as the responsibility of ensuring that you do not do any harm or fail to do something that may likely injure your neighbor. The law however does not give details on who the neighbor is supposed to be. This is one of the reasons that the law should be amended since it does not give a clear definition of who our neighbor is, if it is a person one closely relates to, people defined by property proximity or people you relate with everyday. The next factor considered in duty of care, the claimant must provide evidence that the def endant failed to grant the appropriate standard of care that a sensible person would have provided in similar circumstances.3 The standard of care is explained as a way of measuring how well and much care a reasonable person owes another. There are rules that come with this duty, whether the defendant is a learner, child or a professional because standards differ from one person to another. Some people’s standards of care are higher than others depending on your call of duty or even your line of work. Drivers and doctors, for example, have a higher standard of care toward other people than the reasonable human being because there are responsible to other people’s lives than themselves. It does not matter whether they are learners of profession since there standards of duty are set much higher than other professions. This law is determined by so many factors which makes it ambiguous to prove ones guilt or innocence. Example for people with the skill to do something that any reasonable person would not be able to do is charged with negligence for lack of standard to care of duty. There is also the situation where a child commits a deed with intention of harming others are judged as adults yet there are other rules applied to the same misconduct if the person is of a certain age group. There should be many factors when deciding reasonable standards of duty and care for reasonable people. Example, if there could have been prevention from both parties to avoid more harm and what cautions could be taken by reasonable persons. All the risks involved and the degree of the same by the claimant to reasonable person. Extent of the harm will also be well thought-out in court. The damage to the claimant will be taken into account as there may be two similar damages but of different magnitude which will be unfair to rule equally yet the extent of damage to one was more than the other. It is important to ensure that all the three consideration are taken into ac count so that all the claimants affected by psychiatric disorder caused by negligence are given a fair trial. The claimant must also verify that the events of the defendant were the reason of the plaintiff’s injuries or breakdown. Influencing the cause, known as getting facts, is time and again done by applying but for experiment. Damage would not have happened but for the defendant’s measures. If a driver takes a group of people on a road trip and fails to install seat belts in the car and they

Examining The Computer History Of Microsoft Information Technology Essay

Examining The Computer History Of Microsoft Information Technology Essay Bill Gates is one of the richest people in the world. The way he made his money is by developing technology. He and Paul Allen were the two people who founded Microsoft. But before they founded Microsoft, they worked on the IBM-PC model 5150 and gave IBM a one the PC-DOS operating system for a onetime fee of 50,000 dollars. But they had to make a deal with Seattle Computer Products in order to get this operating system. Then in 1985, with the help of IBM, Gates produced the first retail version on Windows, which was called OS/2. After in 1991 Gates said that the OS/2 partnership was over and he would start working on Windows NT. Windows NT was released in 1993, this version was the first 32-bit version on Windows. From that point on, he helped create multiple other operating systems like windows 95 which introduced the first novel start menu and the included the Internet Explorer internet browser. Later in 2000 Gates stepped down as C.E.O of Microsoft and remained as chairman of the board and chief software architect. In 2006, Gates openly stated that he had many a decision to devote his time more towards his charitable foundation. Gates is still the companys chairman. That is how Bill Gates has made of a contribution to technology. Who is this man? This man was the co-founder and current CEO of Apple Inc. Apple is the innovator of iPods, iPads, iPhones and Mac computers. Apple had other projects like the Apple I and Apple Lisa but they werent as successful. The Macintosh was introduced in 1984. This model included a mouse and a graphical user interface rather than the command-line interface. Apple also created the iPod which allowed people to listen to all their favourite music, and view all their favourite movies and pictures. When the iPod-touch was released it allowed people to do all that and surf the internet with a Wi-Fi connection and download tonnes of apps from the app store on the iPod-touch. The iPhone is the same thing as an iPod-touch but you can text and call people. The iPad is like the iPod-touch but it is larger and you can get 3G service on it. Therefore, I think Steve Jobs has made a significant contribution towards technology. http://en.wikipedia.org/wiki/Steve_Jobs http://en.wikipedia.org/wiki/IPod http://en.wikipedia.org/wiki/Graphical_user_interface http://www.woopidoo.com/biography/steve-jobs/ http://en.wikipedia.org/wiki/Apple_Inc. Magnetic Tape Magnetic Tape is something people use to record music or videos on. This tape was developed in Germany. Separately bought devices can play their music or videos on the Magnetic Tape. Examples of these devices would be VCRs and audio cassette players. The Magnetic Tape was intended to record music at first. This tape was original made by Valdemar Poulsen in 1898. He used iron oxide powder, coating a long strip of paper. But was it was further devolved by a German electronic company called AGE (Allgemeine Elektricitata-Gesellschaft) in 1933. AEG also manufactured the recording machines as well. Later on, people wanted to record video on the magnetic tape, so Ampex made a breakthrough innovation. They used a spinning recording head and a normal tape speeds to achieve a very high head to tape speed that could record and reproduce the high bandwidth. Later on, Sony devolved a helical scan and put it in the tape reels. Finally, these tapes are used for data storage. Some good examples woul d be Computers in 1951. Therefore I think the invention of magnetic tape has contributed to the development of technology greatly. http://en.wikipedia.org/wiki/Magnetic_tape http://www.wisegeek.com/what-is-magnetic-tape.htm http://www.wordiq.com/definition/Magnetic_tape Howard Aiken Howard Akien is the original conceptual designer of the Harvard Mark I computer made by IBM. This computer was built using 765,000 components and a lot of wiring. It was 16m in length and 2.4m in height. Also, it weighed over 4500 kg. This computer was made for calculations. It had 60 sets of 24 switches for entering numbers manually. Also, each number only could be 23 digits long. This machine could calculate 3 additions or subtractions in a second, while a multiplication took 6 seconds, a division taking 15.3. But trigonometric function took over a minute. The way that this computer got its information was from punched paper tape. Therefore, I believe that this computer made a great contribution to technology, as the base of our modern day calculator and computer languages were founded from this innovation. http://en.wikipedia.org/wiki/Howard_H._Aiken http://www.thocp.net/biographies/aiken_howard.html http://inventors.about.com/library/weekly/aa052198.htm Freddy Williams Freddy Williams is an English engineer. He and Tom Kilburn created the Williams or Williams-Kilburn tube, in 1947. This tube was made to store binary data. Each one of these tubes could hold around 512-1024 bits of data. The way this machine stored data was quite fascinating. There would be a cathode ray tube and dots would be drawn on it. The dot becomes positively charged and the area around became negatively charged for a brief moment. This energy could not be transferred and the energy would remain on the surface of the tube for a fraction of a second. This let the device act as the computer memory. The only way to erase a dot is by drawing another dot beside it. Once the memory is safe is when the computer reads the information. Therefore, I believe that this device made a significant contribution to technology because this device laid down the foundation of current day RAM to be developed. http://www.computer50.org/kgill/williams/williams.html http://en.wikipedia.org/wiki/Frederic_Calland_Williams http://en.wikipedia.org/wiki/Williams_tube EDSAC An EDSAC or an Electronic Delay Storage Automatic Calculator was a British computer. The EDSAC was made by Maurice Wilkes and his team at the University of Cambridge Mathematical Laboratory. This was the first practical stored-program computer. This computer uses mercury delay lines for memory. The memory has 1024 locations, while each location has 18 bits. The CPU can hold 71 bits. The only commands that this computer had were: to add, subtract, multiply, collate, shit left, shift right, load multiplier register, store, accumulator, condition skip, read input tape, print character, round accumulator, no-op and stop. The initial orders were hand written on a set of uniselector switches and from there they were loaded into the low words memory at start up. This was the worlds assembler. People say at that moment the global software industry started, people would prepare their programs by punching them on a paper tape. Soon after, the program will be able to be used at this time the pa per was hung on length of line strung up near the paper tape reader. Therefore, I believe that the EDSAC made an important contribution to programming. http://en.wikipedia.org/wiki/Electronic_Delay_Storage_Automatic_Calculator http://www.cl.cam.ac.uk/~mr10/Edsac/edsacposter.pdf http://wiki.answers.com/Q/What_are_the_uses_of_edsac Jacquard loom The Jacquard loom was invented by Joseph Marie Jacquard in 1801. This loom is controlled by punched cards. There are multiple holes punched in each card that make a design of the textile. The way that a hole is punched into the card is by the Bolus hook. Each hook is connected by a harness. These days Jacquards looms are controlled by computers and these computers can have thousands of hooks. The Jacquard loom was the first machine that had the ability to punch cards to control a sequence of operations. This helped the development of computer programming because now programmers didnt have to make their own holes; they could make holes using this loom. Also they could make the holes faster. In conclusion, the Jacquards loom helped the development of programming. http://www.thetapestryhouse.com/aboutproducts/jacquard-loom.html http://en.wikipedia.org/wiki/Jacquard_loom http://www.ideafinder.com/history/inventions/jacquard.htm The Machine That Changed the World Scavenger Hunt Using an internet search engine, find a WWW sites that contains the following statements: 1. Daughter of Lord Byron, mentored by Babbage, called by some the first programmer. Answer: Augusta Ada Lovelace URL: http://wiki.answers.com/ 2. Had a job to speed up the 1890 census and devised a punched-card machine. Answer: Herman Hollerith URL: http://wiki.answers.com/ 3. In 1924 Thomas J. Watson changed the companys name to this name. Answer: International Business Machines. URL: http://en.wikipedia.org/wiki/Thomas_J._Watson 4. A 1973 Federal Court ruling officially credited Dr. John V. Atanasoff with this invention. Answer: first automatic electronic digital computer URL: http://en.wikipedia.org/wiki/John_Vincent_Atanasoff 5. Probably the original mechanical counting device traced back 5,000 years. Answer: The abacus URL: http://www.kraza.itgo.com/html/computer_history.htm 6. This inventor, painter, and sculptor sketched ideas for a mechanical adding machine. Answer: Leonardo da Vinci.   URL: http://wiki.answers.com 7. Created a punched-card system to direct movements of needles, thread, and fabric. Answer: Joseph Jacquard URL: http://wiki.answers.com 8. Howard Aiken completed this electromechanical computer. Answer: The Mark I later making the Mark II Mark III URL: http://wiki.answers.com 9. Dr. John W. ? and Presper ? created the first fully operational electronic computer called ? (3 answers!) Answers: Mauchly and J presper Eckert created the ENIAC (electrical numerical integrator and calculator) URLs: http://inventors.about.com/library/inventors/bleniac.htm 10. IBM introduced the IBM Personal computer or PC in what year. Answer: August 1981 URL: http://www-03.ibm.com/ibm/history/exhibits/pc25/pc25_intro.html 11. Graphic images where each pixel is bit-mapped and take up more memory. Answer: Bitmap Graphic URL: http://wiki.answers.com 12. Graphic images defined by geometric shapes each of which can define the attributes of many pixels. These use less memory. Answer: Vector Graphics URL: http://wiki.answers.com 13. This professor of mathematics joined the Navy in 1943. She led a distinguished career which included developing software for the UNIVAC1. She led the effort to develop the a business language that eventually became COBOL. Answer: Grace Hopper URL: http://www.thocp.net/biographies/hopper_grace.html 14. This object-oriented version of C programming language is used to develop software for PCs such as Fractal Design Painter, Lotus 123, and games. Answer: C++ URL: http://wiki.answers.com 15. The term for communications between remote devices. Answer: Networking URL: http://wiki.answers.com

Reasons to Act Morally Essay -- Ethics Morals Philosophy

Why be moral: A Purpose to Life In our culture, many people are asking the same questions. What makes me better than you? Who says I have to treat you that way? Why does America think it is better than any other country? All of these questions arise from the same question: what are morals? This questions leads to another relevant question: why be moral? What, if anything, makes man (in this paper, I will use the word man in a generic sense meaning the entire human race) a moral creature and thus makes him responsible? However, is there any way we can really know that there are certain inherent laws which govern man, and behind these laws is there a Lawgiver that holds men accountable to these laws? I believe that all these questions can be answered through careful observation and logical thinking. Let us first look at the one thing we know for sure and that is man. We can know this for sure because we are men so we would know how we act. When we associate with others, we do so with some rules of fairness in mind. We treat others in a certain way and expect them to treat us in the same way or we say it is â€Å"unfair† or â€Å"selfish.† We just expect the other person to know that such an act is wrong and that they must play by the same rules that we are. Why do we expect this though? They did not grow up the same way you did. They were not raised by the same parents or even in the same household. So why should one expect them to know the same rules of fairness that you know. If the only basis for your assumption that they should know the rules is because you think the rules are right, then you have no reason to expect them to act that way. However, the other person does indeed know these rule... ...belong to us, we might as well be able to steal because there would be no reason not to. If there was no lawgiver there would be no law, but there obviously is this governing law in men that compels them to do certain things and not do others. If there were not consequences for these actions, anything would basically be moral right. If there was not a being behind the law to enforce it, there would be absolutely no real right or wrong. Everything would be relative, but it is not. There are things that everyone agrees are absolutely good, and absolutely bad. There is no other way around it. The lawgiver has given man a purpose and a reason for life, and it is man’s moral obligation to fulfill that purpose by upholding the law given him. Works Cited / Consulted Lewis C.S. Mere Christianity. New York, New York. Macmillan Publishing Company. 1943. pp 17-39.