Each chapter keeps explanations, definitions and exam advice together—without mixing in quizzes or practice questions.
CHAPTER 1
Characteristics and classification of living organisms
Recognise the characteristics of life and classify organisms using observable features and biological evidence.
Classification places organisms into groups using features they share.
CHAPTER 2
Organisation of the organism
Compare cells, specialised structures, levels of organisation and microscope measurements.
Structure is closely related to function at every level of organisation.
CHAPTER 3
Movement into and out of cells
Explain diffusion, osmosis and active transport across cell membranes.
The direction and energy requirement depend on the concentration gradient.
CHAPTER 4
Biological molecules
Study carbohydrates, fats, proteins, DNA and the chemical tests used to identify nutrients.
Large biological molecules are assembled from smaller building blocks.
CHAPTER 5
Enzymes
Explain enzyme action, specificity, optimum conditions and denaturation.
An enzyme's active site must have a complementary shape to its substrate.
CHAPTER 6
Plant nutrition
Connect photosynthesis, leaf structure, mineral requirements and limiting factors.
Light provides energy; it is not a raw material for photosynthesis.
CHAPTER 7
Human nutrition
Follow food through the digestive system and explain digestion, absorption and assimilation.
Digestion produces small soluble molecules that can be absorbed.
CHAPTER 8
Transport in plants
Explain the roles of xylem, phloem, root hairs, transpiration and translocation.
Xylem carries water and mineral ions; phloem transports sucrose and amino acids.
CHAPTER 9
Transport in animals
Study blood, blood vessels, the heart and double circulation.
Arteries carry blood away from the heart; veins carry it towards the heart.
CHAPTER 10
Diseases and immunity
Understand pathogens, transmission, body defences, vaccination and immunity.
Vaccination prepares memory cells for a faster secondary immune response.
CHAPTER 11
Gas exchange in humans
Relate the structure of the lungs and alveoli to efficient gas exchange.
A large surface area and steep concentration gradients increase diffusion rate.
CHAPTER 12
Respiration
Compare aerobic and anaerobic respiration and explain how released energy is used.
Respiration is a set of chemical reactions in cells, not the movement of air.
CHAPTER 13
Excretion in humans
Explain the removal of metabolic waste and the structure and function of the kidney.
Excretion removes metabolic waste; egestion removes undigested food.
CHAPTER 14
Coordination and response
Explore nervous and hormonal control, sense organs and plant responses.
A coordinated response links a stimulus to an appropriate action.
CHAPTER 15
Drugs
Understand medicinal drugs, antibiotics and the effects of heroin and alcohol.
Antibiotics act against bacteria, not viruses.
CHAPTER 16
Reproduction
Compare asexual and sexual reproduction in plants and humans.
Sexual reproduction produces genetic variation through fusion of gametes.
CHAPTER 17
Inheritance
Use chromosomes, genes, DNA and genetic diagrams to explain inheritance.
A dominant allele is expressed in a heterozygous genotype.
CHAPTER 18
Variation and selection
Distinguish types of variation and explain adaptation, selection and evolution.
Natural selection changes allele frequencies across generations.
CHAPTER 19
Organisms and their environment
Study energy flow, food webs, nutrient cycles and population change.
Energy is lost between trophic levels, so food chains are limited in length.
CHAPTER 20
Human influences on ecosystems
Evaluate food production, habitat loss, pollution and conservation.
Sustainable management meets present needs without preventing future use.
CHAPTER 21
Biotechnology and genetic modification
Explore microorganisms in biotechnology and the principles and impacts of genetic modification.
Genetic modification transfers selected genes to produce a desired characteristic.