CIE A Level Biology Revision Notes 2022

Syllabus Edition

First teaching 2020

Last exams 2024

1. Cell Structure

1.1.1 The Microscope in Cell Studies

1.1.2 Magnification Calculations

1.1.3 Eyepiece Graticules & Stage Micrometers

1.1.4 Resolution & Magnification

1.1.5 Calculating Actual Size

1.2.1 Eukaryotic Cell Structures & Functions

1.2.2 Animal & Plant Cells

1.2.3 The Vital Role of ATP

1.2.4 Prokaryotic v Eukaryotic Cells

1.2.5 Viruses

2. Biological Molecules

2.1.1 Biological Molecule Tests

2.1.2 The Benedict's Test

2.1.3 Testing for Non-Reducing Sugars

2.2.1 Biological Molecules: Key Terms

2.2.2 Covalent Bonds in Polymers

2.2.3 Reducing & Non-Reducing Sugars

2.2.4 The Glycosidic Bond

2.2.5 Starch & Glycogen

2.2.6 Cellulose

2.2.7 Triglycerides

2.2.8 Phospholipids

2.3.1 Amino Acids & the Peptide Bond

2.3.2 The Four Levels of Protein Structure

2.3.3 Protein Shape

2.3.4 Globular & Fibrous Proteins

2.3.5 Haemoglobin

2.3.6 Collagen

2.4.1 Water & the Hydrogen Bond

2.4.2 The Role of Water in Living Organisms

3. Enzymes

3.1.1 Enzymes

3.1.2 Enzyme Action

3.1.3 How Enzymes Work

3.1.4 Measuring Enzyme Activity

3.1.5 Colorimetry

3.2.1 Rate: Temperature

3.2.2 Rate: pH

3.2.3 Rate: Enzyme Concentration

3.2.4 Rate: Substrate Concentration

3.2.5 Rate: Inhibitor Concentration

3.2.6 Vmax & the Michaelis-Menten Constant

3.2.7 Enzyme Inhibitors

3.2.8 Enzyme Activity: Immobilised v Free

4. Cell Membranes & Transport

4.1.1 The Fluid Mosaic Model

4.1.2 Components of Cell Surface Membranes

4.1.3 The Cell Surface Membrane

4.1.4 Cell Signalling

4.2.1 Diffusion

4.2.2 Osmosis

4.2.3 Active Transport

4.2.4 Endocytosis & Exocytosis

4.2.5 Investigating Transport Processes in Plants

4.2.6 Investigating Diffusion

4.2.7 Surface Area to Volume Ratios

4.2.8 Investigating Surface Area

4.2.9 Estimating Water Potential in Plants

4.2.10 Osmosis in Plant Cells

4.2.11 Osmosis in Animals

4.2.12 Comparing Osmosis in Plants & Animals

5. The Mitotic Cell Cycle

5.1.1 Chromosome Structure

5.1.2 Mitosis

5.1.3 The Cell Cycle

5.1.4 The Role of Telomeres

5.1.5 The Role of Stem Cells

5.1.6 How Tumours Form

5.2.1 The Stages of Mitosis

5.2.2 Observing Mitosis

6. Nucleic Acids & Protein Synthesis

6.1.1 Nucleotides

6.1.2 The Structure of DNA

6.1.3 Semi-Conservative DNA Replication

6.1.4 The Structure of RNA

6.2.1 From Gene to Polypeptide

6.2.2 The Universal Genetic Code

6.2.3 Constructing Polypeptides

6.2.4 Transcription

6.2.5 Gene Mutations

7. Transport in Plants

7.1.1 Plant Transverse Sections

7.1.2 Xylem & Phloem Distribution

7.1.3 Xylem Vessels Elements

7.1.4 Phloem Sieve Tube Elements

7.2.1 Water & Mineral Ion Transport in Plants

7.2.2 Transpiration in Plants

7.2.3 Water & the Transpiration Pull

7.2.4 Xerophytic Plant Leaf Adaptations

7.2.5 Movement in the Phloem

7.2.6 The Sucrose Loading Mechanism

7.2.7 Phloem: Mass Flow

8. Transport in Mammals

8.1.1 Circulatory Systems

8.1.2 The Main Blood Vessels

8.1.3 Observing & Drawing Blood Vessels

8.1.4 Blood Vessels: Structures & Functions

8.1.5 Cells of the Blood

8.1.6 The Role of Water in Circulation

8.1.7 Blood, Tissue Fluid & Lymph

8.2.1 Red Blood Cells, Haemoglobin & Oxygen

8.2.2 The Chloride Shift

8.2.3 Plasma & Carbon Dioxide

8.2.4 The Oxygen Dissociation Curve

8.2.5 The Bohr Shift

8.3.1 Structure of the Heart

8.3.2 The Walls of the Heart

8.3.3 The Cardiac Cycle

8.3.4 Heart Action

9. Gas Exchange

9.1.1 The Human Gas Exchange System

9.1.2 Distribution of Tissues

9.1.3 Recognising Tissues

9.1.4 Recognising Structures

9.1.5 Structures & Functions of the Gas Exchange System

9.1.6 Gas Exchange Processes

10. Infectious Diseases

10.1.1 Infectious Diseases

10.1.2 Transmission of Disease

10.1.3 Prevention & Control of Disease

10.2.1 Penicillin

10.2.2 Antibiotic Resistance

10.2.3 Consequences of Antibiotic Resistance

11. Immunity

11.1.1 Phagocytes

11.1.2 Antigens

11.1.3 Primary Immune Response

11.1.4 Memory Cells & Immunity

11.2.1 Antibodies

11.2.2 Making Monoclonal Antibodies

11.2.3 Uses of Monoclonal Antibodies

11.2.4 Types of Immunity

11.2.5 How Vaccines work

11.2.6 Vaccination to Control Disease

12. Energy & Respiration

12.1.1 Energy

12.1.2 ATP

12.1.3 Energy Values of Respiratory Substrates

12.1.4 Respiratory Quotient (RQ)

12.1.5 Investigating RQs

12.2.1 Structure & Function of Mitochondria

12.2.2 The Four Stages in Aerobic Respiration

12.2.3 Aerobic Respiration: Glycolysis

12.2.4 Aerobic Respiration: The Link Reaction

12.2.5 Aerobic Respiration: The Krebs Cycle

12.2.6 Aerobic Respiration: Role of NAD & FAD

12.2.7 Aerobic Respiration: Oxidative Phosphorylation

12.2.8 Anaerobic Respiration

12.2.9 Energy Yield: Aerobic & Anaerobic Respiration

12.2.10 Anaerobic Adaptation of Rice

12.2.11 Aerobic Respiration: Effect of Temperature & Substrate Concentration

13. Photosynthesis

13.1.1 Chloroplasts

13.1.2 Stages of Photosynthesis

13.1.3 Thylakoids & the Stroma

13.1.4 Chloroplast Pigments

13.1.5 Absorption Spectra & Action Spectra

13.1.6 Chromatography of Chloroplast Pigments

13.1.7 Photophosphorylation

13.1.8 The Calvin Cycle

13.2.1 Limiting Factors of Photosynthesis

13.2.2 Investigating the Rate of Photosynthesis

14. Homeostasis

14.1.1 Homeostasis

14.1.2 Production of Urea

14.1.3 Kidney Structure

14.1.4 Nephron Structure

14.1.5 Formation of Urine

14.1.6 Osmoregulation

14.1.7 The Control of Blood Glucose

14.1.8 Test Strips & Biosensors

14.2.1 Stomata

14.2.2 Guard Cells

14.2.3 Abscisic Acid & Stomatal Closure

15. Control & Coordination

15.1.1 The Endocrine System

15.1.2 The Nervous System

15.1.3 Neurones

15.1.4 Sensory Receptor Cells

15.1.5 Sequence of Events Resulting in an Action Potential

15.1.6 Transmission of Nerve Impulses

15.1.7 Speed of Conduction of Impulses

15.1.8 The Refractory Period

15.1.9 Cholinergic Synapses

15.1.10 Stimulating Contraction in Striated Muscle

15.1.11 Ultrastructure of Striated Muscle

15.1.12 Sliding Filament Model of Muscular Contraction

15.2.1 Electrical Communication in the Venus Flytrap

15.2.2 The Role of Auxin in Elongation Growth

15.2.3 The Role of Gibberellin in Germination of Barley

16. Inheritance

16.1.1 Haploid Cells & Diploid Cells

16.1.2 Homologous Chromosomes

16.1.3 Meiosis in Animal & Plant Cells

16.1.4 Identifying the Stages of Meiosis

16.1.5 Meiosis: Sources of Genetic Variation

16.2.1 Key Terms in Genetics

16.2.2 Predicting Inheritance: Monohybrid Crosses

16.2.3 Predicting Inheritance: Dihybrid Crosses

16.2.4 Predicting Inheritance: Test Crosses

16.2.5 Predicting Inheritance: Chi-squared Test

16.2.6 Genes, Proteins & Phenotype

16.2.7 The Role of Gibberellin in Stem Elongation

16.3.1 Gene Control

16.3.2 Lac Operon

16.3.3 Gene Control: Transcription Factors

17. Selection & Evolution

17.1.1 Variation: Phenotype

17.1.2 Variation: Discontinuous & Continuous

17.1.3 Variation: t-test Method

17.1.4 Variation: t-test Worked Example

17.2.1 Natural Selection

17.2.2 Natural Selection: Types of Selection

17.2.3 Natural Selection: Changes in Allele Frequencies

17.2.4 Natural Selection: Antibiotic Resistance

17.2.5 Natural Selection: Hardy-Weinberg Principle

17.2.6 Artificial Selection

17.2.7 Examples of Artificial Selection

17.3.1 Theory of Evolution

17.3.2 Allopatric & Sympatric Speciation

18. Classification, Biodiversity & Conservation

18.1.1 Definitions of Species

18.1.2 The Three Domains: Archaea, Bacteria & Eukarya

18.1.3 Eukarya

18.1.4 Kingdoms

18.1.5 Viruses

18.2.1 Ecosystems & Niches

18.2.2 Biodiversity

18.2.3 Random Sampling

18.2.4 Testing for Distribution & Abundance

18.2.5 Pearson's Linear Correlation

18.2.6 Spearman's Rank Correlation

18.2.7 Simpson's Index

18.3.1 Reasons for Extinction

18.3.2 Reasons for Maintaining Biodiversity

18.3.3 Methods of Conservation

18.3.4 Assisted Reproduction

18.3.5 Controlling Invasive Species

18.3.6 Role of IUCN in Conservation

19. Genetic Technology

19.1.1 Recombinant DNA

19.1.2 Genetic Engineering

19.1.3 Isolating the Desired Gene

19.1.4 Genetic Engineering: Enzymes

19.1.5 Genetic Engineering: Vectors

19.1.6 Genetic Engineering: Promoters & Marker Genes

19.1.7 Gene Editing

19.1.8 Polymerase Chain Reaction

19.1.9 Gel Electrophoresis

19.1.10 Microarrays

19.1.11 Bioinformatics

19.2.1 Recombinant Human Proteins

19.2.2 Genetic Screening

19.2.3 Gene Therapy

19.2.4 Gene Technology in Medicine

19.3.1 Genetically Modified Organisms in Agriculture

19.3.2 Using GMOs in Agriculture

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