Specification points

Cambridge Cambridge IGCSE (9–1) Biology 0970

471 points in 21 topics, with Cambridge's codes and titles.

Grade boundaries·Cambridge command words

Codes and titles are read by a script from Cambridge's published specification and have not been checked by a person. What each point covers is in the specification itself: Cambridge’s specification.

1 Characteristics and classification of living organisms

1.1 Characteristics of living organisms
1.1.1 Characteristics of living organisms
1.2 Concept and uses of classification systems
1.2.1 Classifying organisms by shared features
1.2.2 Species
1.2.3 Binomial naming system
1.2.4 Dichotomous keys
1.2.5 Classification and evolutionary relationships (Supplement)
1.2.6 DNA base sequences in classification (Supplement)
1.2.7 DNA similarity and common ancestry (Supplement)
1.3 Features of organisms
1.3.1 Features of the animal and plant kingdoms
1.3.2 Vertebrate and arthropod groups
1.3.3 Classifying animals and plants
1.3.4 The five kingdoms (Supplement)
1.3.5 Ferns and flowering plants (Supplement)
1.3.6 Classifying into kingdoms and plant groups (Supplement)
1.3.7 Features of viruses (Supplement)

2 Organisation of the organism

2.1 Cell structure
2.1.1 Plant and animal cell structure
2.1.2 Bacterial cell structure
2.1.3 Identifying cell structures in images
2.1.4 Functions of cell structures
2.1.5 New cells from cell division
2.1.6 Specialised cells and their functions
2.1.7 Cells, tissues, organs, organ systems and organisms
2.2 Size of specimens
2.2.1 Magnification formula
2.2.2 Calculating magnification and specimen size
2.2.3 Converting millimetres and micrometres (Supplement)

4 Biological molecules

4.1 Biological molecules
4.1.1 Elements in carbohydrates, fats and proteins
4.1.2 Large molecules from smaller units
4.1.3 Food tests
4.1.4 Structure of DNA (Supplement)

5 Enzymes

5.1 Enzymes
5.1.1 Catalysts
5.1.2 Enzymes as biological catalysts
5.1.3 Why enzymes matter
5.1.4 Enzyme action and the active site
5.1.5 Effect of temperature and pH on enzymes
5.1.6 Active site and enzyme-substrate complex (Supplement)
5.1.7 Enzyme specificity (Supplement)
5.1.8 Temperature, collisions and denaturation (Supplement)
5.1.9 pH, shape and denaturation (Supplement)

6 Plant nutrition

6.1 Photosynthesis
6.1.1 Photosynthesis
6.1.2 Word equation for photosynthesis
6.1.3 Chlorophyll in chloroplasts
6.1.4 Chlorophyll and energy transfer
6.1.5 Uses and storage of photosynthesis products
6.1.6 Nitrate and magnesium ions in plants
6.1.7 Investigating what photosynthesis needs
6.1.8 Factors affecting the rate of photosynthesis
6.1.9 Gas exchange in aquatic plants in light and dark
6.1.10 Balanced equation for photosynthesis (Supplement)
6.1.11 Limiting factors of photosynthesis (Supplement)
6.2 Leaf structure
6.2.1 Leaf adaptations for photosynthesis
6.2.2 Structures in a dicotyledonous leaf
6.2.3 How leaf structures aid photosynthesis

7 Human nutrition

7.1 Diet
7.1.1 Balanced diet
7.1.2 Dietary sources and roles of nutrients
7.1.3 Causes of scurvy and rickets
7.2 Digestive system
7.2.1 Organs of the digestive system
7.2.2 Functions of digestive organs
7.3 Physical digestion
7.3.1 Physical digestion
7.3.2 Physical digestion and surface area
7.3.3 Types of human teeth
7.3.4 Structure of human teeth
7.3.5 Functions of teeth in digestion
7.3.6 Stomach in physical digestion
7.3.7 Bile and emulsification (Supplement)
7.4 Chemical digestion
7.4.1 Chemical digestion
7.4.2 Role of chemical digestion in absorption
7.4.3 Amylase, protease and lipase
7.4.4 Where digestive enzymes are secreted and act
7.4.5 Hydrochloric acid in the stomach
7.4.6 Digestion of starch (Supplement)
7.4.7 Digestion of protein (Supplement)
7.4.8 Bile neutralising stomach acid (Supplement)
7.5 Absorption
7.5.1 Absorption in the small intestine
7.5.2 Water absorption
7.5.3 Villi and microvilli (Supplement)
7.5.4 Structure of a villus (Supplement)
7.5.5 Capillaries and lacteals in villi (Supplement)

9 Transport in animals

9.1 Circulatory systems
9.1.1 Circulatory system
9.1.2 Single circulation in fish (Supplement)
9.1.3 Double circulation in mammals (Supplement)
9.1.4 Advantages of double circulation (Supplement)
9.2 Heart
9.2.1 Structure of the mammalian heart
9.2.2 Arteries and veins
9.2.3 Monitoring heart activity
9.2.4 Physical activity and heart rate
9.2.5 Coronary heart disease and risk factors
9.2.6 Diet and exercise in reducing heart disease
9.2.7 Atrioventricular and semilunar valves (Supplement)
9.2.8 Thickness of heart chamber walls (Supplement)
9.2.9 Role of the septum (Supplement)
9.2.10 How the heart functions (Supplement)
9.2.11 Explaining heart rate changes with activity (Supplement)
9.3 Blood vessels
9.3.1 Structure of arteries, veins and capillaries
9.3.2 Functions of capillaries
9.3.3 Main blood vessels of heart, lungs and kidney
9.3.4 Artery and vein structure and blood pressure (Supplement)
9.3.5 Capillary structure and function (Supplement)
9.3.6 Blood vessels of the liver (Supplement)
9.4 Blood
9.4.1 Components of blood
9.4.2 Identifying red and white blood cells
9.4.3 Functions of blood components
9.4.4 Roles of blood clotting
9.4.5 Lymphocytes and phagocytes (Supplement)
9.4.6 Functions of lymphocytes and phagocytes (Supplement)
9.4.7 Clotting: fibrinogen to fibrin (Supplement)

10 Diseases and immunity

10.1 Diseases and immunity
10.1.1 Pathogens
10.1.2 Transmissible diseases
10.1.3 Direct and indirect transmission
10.1.4 Body defences
10.1.5 Controlling the spread of disease
10.1.6 Active immunity (Supplement)
10.1.7 Antigens (Supplement)
10.1.8 Antibodies (Supplement)
10.1.9 Antibody-antigen specificity (Supplement)
10.1.10 Gaining active immunity (Supplement)
10.1.11 Vaccination (Supplement)
10.1.12 Vaccination and disease control (Supplement)
10.1.13 Passive immunity (Supplement)
10.1.14 Breast-feeding and passive immunity (Supplement)
10.1.15 No memory cells in passive immunity (Supplement)
10.1.16 Cholera (Supplement)
10.1.17 Cholera toxin and its effects (Supplement)

11 Gas exchange in humans

11.1 Gas exchange in humans
11.1.1 Features of gas exchange surfaces
11.1.2 Parts of the breathing system
11.1.3 Investigating inspired and expired air
11.1.4 Composition of inspired and expired air
11.1.5 Physical activity and breathing
11.1.6 Intercostal muscles (Supplement)
11.1.7 Cartilage in the trachea (Supplement)
11.1.8 Mechanism of ventilation (Supplement)
11.1.9 Explaining differences in inspired and expired air (Supplement)
11.1.10 Carbon dioxide and breathing rate (Supplement)
11.1.11 Goblet cells, mucus and cilia (Supplement)

12 Respiration

12.1 Respiration
12.1.1 Uses of energy in organisms
12.1.2 Temperature and yeast respiration
12.2 Aerobic respiration
12.2.1 Aerobic respiration
12.2.2 Word equation for aerobic respiration
12.2.3 Balanced equation for aerobic respiration (Supplement)
12.3 Anaerobic respiration
12.3.1 Anaerobic respiration
12.3.2 Energy yield of anaerobic respiration
12.3.3 Anaerobic respiration in yeast
12.3.4 Anaerobic respiration in muscles
12.3.5 Balanced equation for anaerobic respiration in yeast (Supplement)
12.3.6 Lactic acid and oxygen debt (Supplement)
12.3.7 Removing the oxygen debt (Supplement)

13 Excretion in humans

13.1 Excretion in humans
13.1.1 Excretion of carbon dioxide
13.1.2 Excretion by the kidneys
13.1.3 Kidneys, ureters, bladder and urethra
13.1.4 Kidney structure (Supplement)
13.1.5 The nephron (Supplement)
13.1.6 Liver and assimilation of amino acids (Supplement)
13.1.7 Urea formation (Supplement)
13.1.8 Deamination (Supplement)
13.1.9 Importance of excretion (Supplement)

14 Coordination and response

14.1 Coordination and response
14.1.1 Electrical impulses in neurones
14.1.2 Central and peripheral nervous systems
14.1.3 Role of the nervous system
14.1.4 Sensory, relay and motor neurones
14.1.5 Reflex arc
14.1.6 Reflex actions
14.1.7 Synapses
14.1.8 Structure of a synapse (Supplement)
14.1.9 Events at a synapse (Supplement)
14.1.10 One-way transmission at synapses (Supplement)
14.2 Sense organs
14.2.1 Sense organs
14.2.2 Structures of the eye
14.2.3 Functions of parts of the eye
14.2.4 Pupil reflex
14.2.5 Iris muscles in the pupil reflex (Supplement)
14.2.6 Accommodation (Supplement)
14.2.7 Distribution of rods and cones (Supplement)
14.2.8 Functions of rods and cones (Supplement)
14.2.9 The fovea (Supplement)
14.3 Hormones
14.3.1 Hormones
14.3.2 Endocrine glands and their hormones
14.3.3 Adrenaline and its effects
14.3.4 Nervous versus hormonal control
14.3.5 Glucagon (Supplement)
14.3.6 Adrenaline and metabolic activity (Supplement)
14.4 Homeostasis
14.4.1 Homeostasis
14.4.2 Insulin and blood glucose
14.4.3 Negative feedback (Supplement)
14.4.4 Control of blood glucose (Supplement)
14.4.5 Treating Type 1 diabetes (Supplement)
14.4.6 Structures of the skin (Supplement)
14.4.7 Controlling body temperature (Supplement)
14.4.8 Vasodilation and vasoconstriction (Supplement)
14.5 Tropic responses
14.5.1 Gravitropism
14.5.2 Phototropism
14.5.3 Investigating tropisms in shoots and roots
14.5.4 Tropisms as chemical control of growth (Supplement)
14.5.5 Auxin and shoot growth (Supplement)

15 Drugs

15.1 Drugs
15.1.1 Drugs
15.1.2 Antibiotics for bacterial infections
15.1.3 Antibiotic resistance
15.1.4 Antibiotics and viruses
15.1.5 Limiting antibiotic resistance (Supplement)

16 Reproduction

16.1 Asexual reproduction
16.1.1 Asexual reproduction
16.1.2 Examples of asexual reproduction
16.1.3 Pros and cons of asexual reproduction (Supplement)
16.2 Sexual reproduction
16.2.1 Sexual reproduction
16.2.2 Fertilisation
16.2.3 Haploid gametes and diploid zygotes (Supplement)
16.2.4 Pros and cons of sexual reproduction (Supplement)
16.3 Sexual reproduction in plants
16.3.1 Parts of an insect-pollinated flower
16.3.2 Functions of flower parts
16.3.3 Anthers and stigmas of wind-pollinated flowers
16.3.4 Pollen of insect- and wind-pollinated flowers
16.3.5 Pollination
16.3.6 Fertilisation in flowering plants
16.3.7 Adaptations of insect- and wind-pollinated flowers
16.3.8 Conditions for seed germination
16.3.9 Self-pollination (Supplement)
16.3.10 Cross-pollination (Supplement)
16.3.11 Effects of self- and cross-pollination on populations (Supplement)
16.3.12 Pollen tube growth and fertilisation (Supplement)
16.4 Sexual reproduction in humans
16.4.1 Male reproductive system
16.4.2 Female reproductive system
16.4.3 Human fertilisation
16.4.4 Adaptations of sperm
16.4.5 Adaptations of egg cells
16.4.6 Comparing male and female gametes
16.4.7 Embryo formation and implantation
16.4.8 Structures supporting the fetus
16.4.9 Placenta and umbilical cord exchange (Supplement)
16.4.10 Pathogens and toxins crossing the placenta (Supplement)
16.5 Sex hormones in humans
16.5.1 Testosterone, oestrogen and puberty
16.5.2 The menstrual cycle
16.5.3 Production of oestrogen and progesterone (Supplement)
16.5.4 Hormonal control of the menstrual cycle and pregnancy (Supplement)
16.6 Sexually transmitted infections
16.6.1 Sexually transmitted infections
16.6.2 HIV as an STI pathogen
16.6.3 HIV and AIDS
16.6.4 Transmission of HIV
16.6.5 Controlling the spread of STIs

17 Inheritance

17.1 Chromosomes, genes and proteins
17.1.1 Chromosomes, DNA and genes
17.1.2 Genes
17.1.3 Alleles
17.1.4 Inheritance of sex
17.1.5 Base sequence and amino acid sequence (Supplement)
17.1.6 Amino acid sequence and protein shape (Supplement)
17.1.7 DNA controlling cell function (Supplement)
17.1.8 Protein synthesis (Supplement)
17.1.9 Gene expression in specialised cells (Supplement)
17.1.10 Haploid nucleus (Supplement)
17.1.11 Diploid nucleus (Supplement)
17.1.12 Chromosome pairs in diploid cells (Supplement)
17.2 Mitosis
17.2.1 Mitosis (Supplement)
17.2.2 Roles of mitosis (Supplement)
17.2.3 Chromosome replication before mitosis (Supplement)
17.2.4 Chromosome separation in mitosis (Supplement)
17.2.5 Stem cells (Supplement)
17.3 Meiosis
17.3.1 Meiosis and gametes (Supplement)
17.3.2 Meiosis as reduction division (Supplement)
17.4 Monohybrid inheritance
17.4.1 Inheritance
17.4.2 Genotype
17.4.3 Phenotype
17.4.4 Homozygous
17.4.5 Pure-breeding
17.4.6 Heterozygous
17.4.7 Heterozygotes are not pure-breeding
17.4.8 Dominant alleles
17.4.9 Recessive alleles
17.4.10 Pedigree diagrams
17.4.11 Monohybrid crosses and ratios
17.4.12 Punnett squares
17.4.13 Test crosses (Supplement)
17.4.14 Codominance (Supplement)
17.4.15 ABO blood groups (Supplement)
17.4.16 Sex-linked characteristics (Supplement)
17.4.17 Red-green colour blindness (Supplement)
17.4.18 Crosses with codominance or sex linkage (Supplement)

19 Organisms and their environment

19.1 Energy flow
19.1.1 The Sun as energy source
19.1.2 Energy flow through organisms
19.2 Food chains and food webs
19.2.1 Food chains
19.2.2 Constructing food chains
19.2.3 Food webs
19.2.4 Producers
19.2.5 Consumers
19.2.6 Levels of consumers
19.2.7 Herbivores
19.2.8 Carnivores
19.2.9 Decomposers
19.2.10 Human impact on food webs
19.2.11 Pyramids of numbers and biomass
19.2.12 Pyramids of biomass versus numbers
19.2.13 Trophic levels
19.2.14 Identifying trophic levels
19.2.15 Pyramids of energy (Supplement)
19.2.16 Advantages of pyramids of energy (Supplement)
19.2.17 Inefficient energy transfer between trophic levels (Supplement)
19.2.18 Why food chains are short (Supplement)
19.2.19 Energy efficiency of eating crops versus livestock (Supplement)
19.3 Nutrient cycles
19.3.1 The carbon cycle
19.3.2 The nitrogen cycle (Supplement)
19.3.3 Microorganisms in the nitrogen cycle (Supplement)
19.4 Populations
19.4.1 Populations
19.4.2 Communities
19.4.3 Ecosystems
19.4.4 Factors affecting population growth
19.4.5 Phases of the sigmoid growth curve
19.4.6 Interpreting population growth graphs
19.4.7 Causes of each growth phase (Supplement)

20 Human influences on ecosystems

20.1 Food supply
20.1.1 Increasing food production
20.1.2 Pros and cons of monocultures
20.1.3 Pros and cons of intensive livestock production
20.2 Habitat destruction
20.2.1 Biodiversity
20.2.2 Reasons for habitat destruction
20.2.3 Human impact through food webs
20.2.4 Effects of deforestation
20.3 Pollution
20.3.1 Sewage and fertiliser in aquatic ecosystems
20.3.2 Non-biodegradable plastics
20.3.3 Methane and carbon dioxide pollution
20.3.4 Eutrophication (Supplement)
20.4 Conservation
20.4.1 Sustainable resources
20.4.2 Sustainable forests and fish stocks
20.4.3 Why species become endangered or extinct
20.4.4 Conserving endangered species
20.4.5 Conserving forests (Supplement)
20.4.6 Conserving fish stocks (Supplement)
20.4.7 Reasons for conservation programmes (Supplement)
20.4.8 Artificial insemination and IVF in captive breeding (Supplement)
20.4.9 Risks of small population size (Supplement)

21 Biotechnology and genetic modification

21.1 Biotechnology and genetic modification
21.1.1 Bacteria in biotechnology
21.1.2 Why bacteria are useful in biotechnology (Supplement)
21.2 Biotechnology
21.2.1 Yeast and biofuel production
21.2.2 Yeast in bread-making
21.2.3 Pectinase in fruit juice production
21.2.4 Biological washing powders
21.2.5 Lactase and lactose-free milk (Supplement)
21.2.6 Fermenters for large-scale production (Supplement)
21.2.7 Controlling fermenter conditions (Supplement)
21.3 Genetic modification
21.3.1 Genetic modification
21.3.2 Examples of genetic modification
21.3.3 Process of genetic modification (Supplement)
21.3.4 Pros and cons of GM crops (Supplement)