Life processes and cell activity

a the life processes common to plants and animals;

b that organ systems are adapted for their roles in life processes;

c that plant and animal cells have some similarities in structure;

d how substances enter and leave cells through the cell membrane by diffusion, osmosis and active transport;

e that the nucleus contains chromosomes that carry the genes;

f how cells divide by mitosis so that growth takes place, and by meiosis to produce gametes.

2. Humans as organisms

nutrition

a the structure of the human digestive system;

b the processes involved in digestion, including the roles of enzymes, stomach acid and bile;

circulation

c the structure of the human circulatory system, including the composition and functions of blood;

breathing

d the structure of the thorax;

e how breathing, including ventilation of the lungs, takes place;

respiration

f that respiration may be either aerobic or anaerobic, depending on the availability of oxygen;

g that an 'oxygen debt' may occur in muscles during vigorous exercise;

nervous system

h the pathway taken by impulses in response to a variety of stimuli, including touch, taste, smell, light, sound and balance;

i how the reflex arc, which involves a nerve impulse carried via neurones and across synapses, makes possible rapid response to a stimulus;

j the structure of the eye and how it functions in response to light;

hormones

k the way in which hormonal control occurs, including the effects of insulin and sex hormones;

l some medical uses of hormones, including the control and promotion of fertility and the treatment of diabetes;

homeostasis

m the importance of maintaining a constant internal environment;

n how waste products of body functions are removed by the lungs and kidneys;

o how the kidneys regulate the water content of the body;

p how humans maintain a constant body temperature;

health

q the defence mechanisms of the body, including the role of the skin, blood and mucous membranes of the respiratory tract;

r the effects of solvents, alcohol, tobacco and other drugs on body functions.

3. Green plants as organisms

nutrition

a the reactants in, and products of, photosynthesis;

b that the rate of photosynthesis may be limited by light intensity, carbon dioxide concentration or temperature;

c how the products of photosynthesis are utilised by the plant;

d the importance to healthy plant growth of the uptake and utilisation of mineral salts;

hormones

e the hormonal control of plant growth and development, including commercial applications;

transport and water relations

f how plants take up water and transpire;

g the importance of water in the support of plant tissues;

h that substances required for growth and reproduction are transported within plants.

4. Variation, inheritance and evolution

variation

a how variation may arise from both genetic and environmental causes;

b that sexual reproduction is a source of genetic variation, while asexual reproduction produces clones;

c that mutation is a source of genetic variation and has a number of causes;

inheritance

d how gender is determined in humans;

e the mechanism of monohybrid inheritance where there are dominant and recessive alleles;

f that some diseases can be inherited;

g that the gene is a section of DNA;

h the basic principles of cloning, selective breeding and genetic engineering;

evolution

i the fossil record as evidence for evolution;

j how variation and selection may lead to evolution or to extinction.

5. Living things in their environment

adaptation and competition

a how the distribution and relative abundance of organisms in a habitat can be explained in terms of adaptation, competition and predation;

b how the impact of human activity on the environment is related to population size, economic factors and industrial requirements;

energy and nutrient transfer

c how food chains may be described quantitatively using pyramids of numbers and pyramids of biomass;

d how energy is transferred through an ecosystem;

e the role of microbes and other organisms in the decomposition of organic materials and in the cycling of carbon and nitrogen;

f how food production can be managed to improve the efficiency of energy transfer.