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The many different types of relationships and interactions between organisms.
The membranes of different types of cells and how they are involved in many different functions.
The importance of ions in biology.
How energy is transferred within and between organisms.
How cells and organisms carry out exchanges with their external environment
to maintain their internal environment.
The importance to humans of the control of growth, reproduction and development of organisms, including themselves.
The importance of responses to changes in the internal and external environment of an organism.
The ways in which water and the regulation of water content are important to organisms.
The control of processes in cells and the importance of these controls.
The importance of receptors in living organisms.
The importance of movement in living organisms.
The importance of diffusion in organisms.
The importance of nucleotides, molecules derived from nucleotides and nucleic acids in keeping organisms alive.
The importance of nitrogen-containing substances in biological systems.
The importance of interactions between cells and between organisms.
The importance of complementary shapes of molecules in organisms.
The importance of the control of movement in cells and organisms.
The importance of bonds and bonding in organisms.
The importance of DNA as an information-carrying molecule and its use in gene technologies.
The causes and importance of variation and diversity in organisms.
The functions of enzymes and their importance in organisms.
The uses and importance of ATP in organisms.
The importance of ions in metabolic processes.
The importance of cycles in biology.

The many different types of relationships and interactions between organisms.
1.P Pathogens and effects on host.
2.T Taxonomy.
2.C Classification and evolution.
2.I Inheritance and evolution.
2.Gc Genetic code, universal.
2.B Behaviour.
2.Ev Populations and evolution, variation between individuals within a species.
3.BP Relationships within ecosystems − eg predator / prey.
3.E Energy transfer in ecosystems.
3.N Nutrient cycles, the organisms involved.
3.S Succession, biodiversity, species and individuals in a community.
4.H Human impacts on the environment and its effect on relationships between organisms − including farming.
4.Gt Gene technology and GMO and selective breeding.
4.Ar Antibiotic resistance.
The membranes of different types of cells and how they are involved in many different functions.
1.M Membrane function as selectively permeable barrier.
1.T Transport mechanisms across membranes.
1.CT Absorption and co-transport of sodium ions and glucose.
2.P Photosynthesis, chloroplast, thylakoids.
2.R Respiration, mitochondrion and cristae.
2.Ps Protein secretion, RER, SER and Golgi.
3.A Surface receptors / antigen and immune response.
3.CD Cell division.
3.B Vertical and horizontal transmission − membranes and bacteria.
3.Pc Pacinian corpuscle.
4.Tr Tropisms − movement of IAA.
4.N Nerve impulses / action potentials.
4.S Synaptic transmission.
4.Mc Muscle contraction, calcium ion movement / storage.
4.H Hormones - eg Blood glucose regulation − insulin and glucagon.
4.O Osmosis, including water movement in plants.
Breadth, one mark for use of an example from each of the following approaches: 1. Membranes − basic functions 2. Organelle membranes 3. Cell surface membranes 4. Processes − eg protein secretion, synaptic transmission, cell division
The importance of ions in biology.
3.1.3. and 3.2.2. Phosphate in structure of phospholipids, structure of membranes, nucleotides, DNA and RNA
3.1.3 Water potentials and osmosis, chloride ions and cholera; Co-transport involving sodium ions
3.2.4. Haemoglobin and iron
3.2.7. Passage of water through plants, symplast and root pressure
3.4.1. ATP and ADP
3.4.3 Protons in photosynthesis, including reduced NADP and phosphorylated intermediates
3.4.4. Protons in respiration, reduced NADS and FAD and phosphorylated intermediates; Glycolysis and lactate
3.4.5. Use of (NPK) fertilisers
3.4.6. Nitrogen cycle
3.5.1. Chemoreceptors, heart rate and Pacinian function
3.5.2. Nerve impulses and synapses
3.5.3. Calcium ions and muscle contraction, and phosphate from ATP
3.5.8. Genetic fingerprinting, electrophoresis
How energy is transferred within and between organisms.
Photosynthesis
Energy transfer through ecosystems
Food production
Digestion (as in fuel)
Absorption (by cells)
Mass transport
Respiration
ATP
Stimuli and responses
Muscle contraction
Nerve impulses
How cells and organisms carry out exchanges with their external environment to maintain their internal environment.
Homeostasis (concept of)
Digestion and absorption
Cells
Lung function
Gas exchange
Passage of water through plant
Nutrient cycles
Response to stimuli
Neurones
Temperature control
Tissue fluid and its formation
Control of blood glucose concentration
Negative feedback
Gene expression
The importance to humans of the control of growth, reproduction and development of organisms, including themselves.
3.1.1. Pathogens (and invasion of human tissues)
3.2.10 Antibiotic resistance − control of bacterial growth
3.1.3. Cholera
3.1.6. Immune response and vaccination (to control growth of pathogens)
3.2.11. Human influence on biodiversity
3.4.1. Human populations
3.4.5. Humans and farming practices
3.2.3 selective breeding
3.4.6. Use of fertilisers and pesticides
3.4.7. Succession − control of
3.4.8. Genetics − prediction of inherited conditions
3.5.7. Control of gene expression − stem cells
3.5.7. Regulation of gene expression − prevention, treatment and cure of cancer
3.2.5 Mitosis and cancer
3.5.8 Gene cloning and transfer
3.5.8 Gene therapy
The importance of responses to changes in the internal and external environment of an organism.
3.1.3. Transport in and out of cells (of specific substances)
3.1.6. Immune response
3.2.4. Haemoglobin
3.2.7. Transpiration − response to environmental factors − gas exchange in plants
3.2.9. Behaviour
3.2.10. Adaptation and selection
3.4.8. Changes in populations − selection pressures
3.5.1. Responses to stimuli − plants and tropisms − control of heart rate
3.5.1. Taxes and kineses
3.5.1. Receptors
3.5.2. Control of Heart Rate
3.5.1 and 2 Simple reflexes and neurones and synapses
3.5.2 and 5.4 Hormones and responses
3.5.2 Chemical mediators
3.5.4 Homeostasis − response to changes in internal environments
3.5.5 Feedback
3.5.7 Gene expression as part of response
The ways in which water and the regulation of water content are important to organisms.
3.1.1 Monomers and polymers – carbohydrates – lipids – proteins
3.1.7 Water
3.2.3 Transport across membranes – osmosis – water potentials
3.3.2 Gas exchange – plants
3.3.2 Gas exchange – fish
3.3.2 Gas exchange – insects
3.3.4.1 Mass transport in animals - blood – circulation
3.3.4.1 Mass transport in animals – tissue fluid and formation
3.3.4.2 Mass transport in plants – transpiration stream
3.3.4.2 Mass transport in plants – translocation
3.5.1 Photosynthesis
3.5.4 Nutrient cycles – leaching and eutrophication
3.6.1 Growth responses in plants
3.6.4 Homeostasis
3.6.4.3 Control of blood and water potential
The control of processes in cells and the importance of these controls.
3.1.3. and 3.2.4. Organelles and processes
3.1.3. Transport across membranes
3.1.3. Cholera
3.1.5. Immune response
3.2.2. Meiosis
3.2.5. Mitosis and cell cycle and DNA replication
3.2.7. Passage of water through plant
3.4.2. ATP
3.4.3. Photosynthesis
3.4.3. Respiration
3.2.10. Antibiotics and genetic variation
3.4.8. Inheritance
3.5.1. Receptors
3.5.2. Nerve impulses and synapses
3.2.7. Passage of water through plant
3.5.3. Muscle contraction
3.5.4. Control of blood glucose concentration – hormones – plant growth substances
3.2.6. Cell differentiation
3.5.6. Polypeptide synthesis and gene mutations
3.5.7. Gene expression
3.5.8. Gene therapy
The importance of receptors in living organisms.
3.1.4.2 Enzymes
3.2.1.2 Structure of prokaryotic cells and of viruses
3.2.3 Transport across cell membranes
3.2.4 Cell recognition and the immune system
3.3.4.1 Mass transport in animals
3.4.2 DNA and protein synthesis
3.5.1 Photosynthesis
3.5.2 Respiration
3.6.1.1 Survival and response
3.6.1.2 Receptors
3.6.1.3 Control of heart rate
3.6.2.1 Nerve impulses
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscles
3.6.4.1 Principles of homeostasis
3.6.4.2 Control of blood glucose concentration
3.6.4.3 Control of blood water potential
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
The importance of movement in living organisms.
3.1.4.2 Enzyme-catalysed reactions
3.1.5.2 DNA replication
3.1.6 ATP
3.2.2 Cell division
3.2.3 Transport across membranes
3.2.4 Immune response
3.2.2 Gas exchange
3.3.3 Digestion and absorption
3.3.4.1, 4.2 Mass transport
3.4.2 DNA and protein synthesis
3.4.3 Meiosis
3.5.1 Photosynthesis
3.5.2 Respiration
3.6.1 Survival and response
3.6.1.2 Receptors
3.6.1.3 Control of heart rate
3.6.2.1 Nerve impulses
3.6.2.2 Synapses
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscle
3.6.4.2 Control of blood glucose concentration
3.6.4.3 Control of blood water potential
3.7.3 Evolution (population isolation and movement between)
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
The importance of diffusion in organisms.
3.1.7 and 3.1.8 water and inorganic ions
3.2.3 transport across membranes
3.3.2 gas exchange
3.3.3 digestion and absorption
3.3.4.1 mass transport in animals
3.3.4.2 mass transport in plants
3.4.2 DNA and protein synthesis
3.5.1 photosynthesis
3.5.2 respiration
3.5.4 nutrient cycles
3.6.1.1 plant responses to stimuli
3.6.1.2 receptors
3.6.2.1 nerve impulses
3.6.2.2 synaptic transmission
3.6.3 muscle contraction
3.6.4.1 and 4.2 control of blood glucose concentration
3.6.4.3 control of blood water potential
The importance of nucleotides, molecules derived from nucleotides and nucleic acids in keeping organisms alive.
3.1.6 ATP
3.1.4.2 Enzymes – ATP, phosphorylation and activation energy
3.1.5 Nucleic acids – information carrying molecules
3.2.2 Mitosis
3.2.3 Transport across membranes – active transport and co-transport
3.3.3 Absorption
3.4.1 DNA, genes and chromosomes
3.4.2 DNA and protein synthesis – ribosomes as nucleic acids – mRNA, tRNA – etc.
3.4.3 Genetic diversity – mutations
3.4. Meiosis
3.4.4 Diversity and adaptation
3.5.1 Photosynthesis
3.5.2 Respiration
3.6.2 Nerve impulses
3.6.3 Muscle contraction
3.6.4.2 Control of blood glucose – second messenger and cAMP
3.6.4.3 Control of blood water potential
3.8.1 Control of gene expression – Mutations
3.8.2 Gene expression
3.8.2.2 Regulation transcription and translation
The importance of nitrogen-containing substances in biological systems.
3.1.4 and 3.1.4.2 proteins and enzymes
3.1.5 nucleic acids
3.1.5.2 DNA replication
3.1.6 ATP
3.2.1.1 ribosomes
3.2.2 cell division
3.2.3 transport across membranes
3.2.4 immune response
3.3.3 digestion and absorption
3.3.4.1 haemoglobin
3.4.1 genes and chromosomes
3.4.2 protein synthesis
3.4.3 mutation
3.4.7 investigating diversity
3.5.1 photosynthesis
3.5.2 respiration
3.5.4 nitrogen cycle
3.6.2 nervous coordination
3.6.3 muscles
3.6.4.2 control of blood glucose (and peptide / protein hormones)
3.7.1 inheritance
3.8.1 alteration of DNA sequences
3.8.2.2 regulation of transcription and translation
The importance of interactions between cells and between organisms.
3.2.1.2 Viruses
3.2.4 Cell recognition, immune system, HIV
3.3.2 Gas exchange
3.3.4.1 Mass transport in animals
3.3.4.2 Mass transport in plants
3.4.4 Genetic diversity and adaptation
3.4.5 Species and taxonomy (courtship behaviour)
3.4.6 Biodiversity within a community
3.5.3 Energy and ecosystems
3.5.4 Nutrient cycles
3.6.1.1 Survival and response
3.6.1.2 Receptors
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscles are stimulated
3.6.4.2 Control of blood glucose
3.6.4.3 Control of blood water potential
3.7.1 Inheritance
3.7.2 Populations in ecosystems
3.7.3 Evolution and speciation
3.7.4 Populations in ecosystems
3.8.2.3 Gene expression and cancer
The importance of complementary shapes of molecules in organisms.
3.1.4.2 Many proteins are enzymes
3.1.5.1 Structure of DNA and RNA
3.1.5.2 DNA replication
3.1.6 ATP
3.2.2 All cells arise from other cells
3.2.3 Transport across cell membranes
3.2.4 Cell recognition and the immune system
3.3.3 Digestion and absorption
3.4.1 DNA, genes and chromosomes
3.4.2 DNA and protein synthesis
3.4.3 Genetic diversity can arise as a result of mutation or during meiosis
3.5.1 Photosynthesis
3.5.2 Respiration
3.6.1.2 Receptors
3.6.2.1 Nerve impulses
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscles are stimulated to contract by nerves and act as effectors
3.6.4.2 Control of blood glucose concentration
3.6.4.3 Control of blood water potential
3.8.1 Alteration of the sequence of bases in DNA can alter the structure of proteins
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
The importance of the control of movement in cells and organisms.
3.1.4.2 Enzymes and control of action
3.1.5.2 DNA replication
3.2.2 Mitosis, binary fission
3.2.3 Transport across membranes
3.2.4 Cell recognition and the immune system
3.3.2 Gas exchange
3.3.3 Digestion and absorption
3.3.4.1 Mass transport in animals
3.3.4.2 Mass transport in plants
3.4.2 DNA and protein synthesis
3.4.3 Meiosis
3.5.1 Photosynthesis
3.5.2 Respiration
3.6.1.1 Survival and response
3.6.1.2 Receptors
3.6.1.3 Control of heart rate
3.6.2.1 Nervous impulses
3.6.2.2 Synaptic transmission
3.6.3 Muscle contraction
3.6.4.2 Control of blood glucose
3.6.4.3 Control of blood water potential
3.7.1 Inheritance
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
The importance of bonds and bonding in organisms.
3.1.1 Monomers and polymers
3.1.2 Carbohydrates
3.1.3 Lipids
3.1.4.1 General properties of proteins
3.1.4.2 Many proteins are enzymes
3.1.5.1 Structure of DNA and RNA
3.1.5.2 DNA replication
3.1.6 ATP
3.1.7 Water – cohesion
3.2.2 Mitosis
3.2.3 Transport across cell membranes
3.2.4 Cell recognition and the immune system
3.3.3 Digestion and absorption
3.3.4.1 Mass transport in animals – haemoglobin
3.3.4.2 Mass transport in plants
3.4.2 DNA and protein synthesis
3.4.3 Mutation and meiosis
3.5.1 Photosynthesis
3.5.2 Respiration
3.5.4 Nutrient cycles
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscles
3.6.4.2 Control of blood glucose concentration
3.6.4.3 Control of blood water potential
3.8.1 Mutations
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
3.8.4.1 Recombinant DNA technology
The importance of DNA as an information-carrying molecule and its use in gene technologies.
3.1.5.1 Structure of DNA
3.1.5.2 DNA replication
3.2.1.1 DNA in mitochondria (and chloroplasts)
3.2.1.2 Prokaryotic DNA
3.2.2 DNA replication in interphase and binary fission
3.4.1 DNA, genes and chromosomes
3.4.2 DNA and protein synthesis
3.4.3 Genetic diversity and meiosis
3.4.4 Genetic diversity and adaptation
3.4.7 Investigating diversity
3.7.1 Inheritance
3.7.3 Evolution may lead to speciation
3.8.1 Alteration of the sequence of bases in DNA can alter the structure of proteins
3.8.2.1 Most of a cell’s DNA is not translated
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
3.8.3 Using genome projects
3.8.4.1 Recombinant DNA technology
3.8.4.2 Differences in DNA between individuals of the same species can be exploited for identification and diagnosis of heritable conditions
3.8.4.3 Genetic fingerprinting
The causes and importance of variation and diversity in organisms.
3.1.4.1 Proteins have a variety of functions in all living organisms
3.2.4 Effect of antigen variability on disease and disease prevention
3.4.3 Genetic diversity from mutation
3.4.3 Genetic diversity from meiosis
3.4.4 Genetic diversity and adaptation
3.4.5 Courtship behaviour
3.4.6 Biodiversity within a community
3.4.7 Investigating diversity
3.5.3 Energy and ecosystems – farming practices
3.6.3 Slow and fast twitch muscles
3.7.1 Inheritance
3.7.2 Populations
3.7.3 Evolution leading to speciation
3.7.4 Populations in ecosystems
3.8.1 Alteration of base sequences
3.8.2.2 Regulation of transcription and translation
3.8.2.3 Gene expression and cancer
3.8.4.1 Recombinant DNA technology
3.8.4.2 Identification of heritable conditions
3.8.4.3 Genetic fingerprinting
The functions of enzymes and their importance in organisms.
3.1.4.2 Many proteins are enzymes
3.1.5.2 DNA replication
3.1.6 ATP
3.2.4 Cell recognition and the immune system (lysozyme)
3.3.3 Digestion and absorption
3.4.2 DNA and protein synthesis
3.4.4 Genetic diversity and adaptation (penicillinase in bacteria)
3.5.1 Photosynthesis
3.5.2 Respiration
3.5.4 Nutrient cycles
3.6.2.2 Synaptic transmission
3.6.3 Muscles
3.6.4.2 Control of blood glucose
3.8.4.1 Recombinant DNA technology
3.8.4.3 DNA fingerprinting
The uses and importance of ATP in organisms.
3.1.5.2 DNA replication
3.1.6 ATP
3.2.2 All cells arise from other cells (mitosis)
3.2.3 Active transport
3.3.3 Digestion and absorption − co-transport
3.3.4.2 Mass transport in plants
3.4.2 DNA and protein synthesis
3.4.3 Meiosis
3.5.1 Photosynthesis
3.5.2 Respiration
3.5.4 Nutrient cycles − nitrogen fixation
3.6.2.1 Nerve impulses − resting potential
3.6.2.2 Synaptic transmission
3.6.3 Myofibril/muscle contraction
3.6.4.2 Control of blood glucose concentration (2nd messenger model)
3.6.4.3 Control of blood water potential
The importance of ions in metabolic processes.
3.1.4.2 Many proteins are enzymes (H and denaturation)
3.1.5.2 DNA replication
3.1.6 ATP
3.1.8 Inorganic ions
3.2.3 Transport across cell membranes
3.3.3 Digestion and absorption
3.3.4.1 Mass transport in animals
3.3.4.2 Mass transport in plants
3.4.2 DNA and protein synthesis
3.5.1 Photosynthesis
3.5.2 Respiration
3.5.4 Nutrient cycles
3.6.1.1 Survival and response
3.6.1.2 Receptors
3.6.2.1 Nerve impulses
3.6.2.2 Synaptic transmission
3.6.3 Skeletal muscles are stimulated to contract by nerves and act as effectors
3.6.4.3 Control of blood water potential
3.8.4.3 Genetic fingerprinting
The importance of cycles in biology.
3.1.1 Monomers and polymers
3.1.4.2 Many proteins are enzymes
3.1.5.2 DNA replication
3.1.6 ATP
3.2.2 All cells arise from other cells
3.3.2 Gas exchange – mechanism of breathing
3.3.4.1 Cardiac cycle and blood circulation and 3.6.1.3 Control of heart rate
3.4.3 Meiosis
3.5.1 Photosynthesis – light independent reaction
3.5.2 Respiration – Krebs cycle and electron transport chain
3.5.4 Nutrient cycles
3.6.2.1 Nerve impulses
3.6.2.2 Synaptic transmission
3.6.3 Muscle contraction
3.6.4.1 Negative feedback
3.6.4.2 Control of blood glucose concentration
3.6.4.3 Control of blood water potential
3.7.4 Populations in ecosystems – predation
3.8.4.1 Recombinant DNA technology – PCR