Cambridge (CIE) A Level Biology Revision Notes 2023

1. Cell Structure

2. Biological Molecules

Biological Molecule Tests

The Benedict's Test

Testing for Non-Reducing Sugars

Biological Molecules: Key Terms

Covalent Bonds in Polymers

Reducing & Non-Reducing Sugars

Amino Acids & the Peptide Bond

The Four Levels of Protein Structure

Protein Shape

Globular & Fibrous Proteins

Haemoglobin

Collagen

Water & the Hydrogen Bond

The Role of Water in Living Organisms

3. Enzymes

Enzymes

Enzyme Action

How Enzymes Work

Measuring Enzyme Activity

Colorimetry

Rate: Temperature

Rate: pH

Rate: Enzyme Concentration

Rate: Substrate Concentration

Rate: Inhibitor Concentration

Vmax & the Michaelis-Menten Constant

Enzyme Inhibitors

Enzyme Activity: Immobilised v Free

4. Cell Membranes & Transport

The Fluid Mosaic Model

Components of Cell Surface Membranes

The Cell Surface Membrane

Endocytosis & Exocytosis

Investigating Transport Processes in Plants

Investigating Diffusion

Surface Area to Volume Ratios

Investigating Surface Area

Estimating Water Potential in Plants

Osmosis in Plant Cells

Osmosis in Animals

Comparing Osmosis in Plants & Animals

5. The Mitotic Cell Cycle

Chromosome Structure

Mitosis

The Cell Cycle

The Role of Telomeres

The Role of Stem Cells

How Tumours Form

The Stages of Mitosis

Observing Mitosis

6. Nucleic Acids & Protein Synthesis

Nucleotides

The Structure of DNA

Semi-Conservative DNA Replication

The Structure of RNA

From Gene to Polypeptide

The Universal Genetic Code

Constructing Polypeptides

Transcription

Gene Mutations

7. Transport in Plants

Plant Transverse Sections

Xylem & Phloem Distribution

Xylem Vessels Elements

Phloem Sieve Tube Elements

Water & Mineral Ion Transport in Plants

Transpiration in Plants

Water & the Transpiration Pull

Xerophytic Plant Leaf Adaptations

Movement in the Phloem

The Sucrose Loading Mechanism

Phloem: Mass Flow

8. Transport in Mammals

Circulatory Systems

The Main Blood Vessels

Observing & Drawing Blood Vessels

Blood Vessels: Structures & Functions

Cells of the Blood

The Role of Water in Circulation

Blood & Tissue Fluid

Red Blood Cells, Haemoglobin & Oxygen

The Chloride Shift

Plasma & Carbon Dioxide

The Oxygen Dissociation Curve

The Bohr Shift

Structure of the Heart

The Walls of the Heart

The Cardiac Cycle

Heart Action

9. Gas Exchange

The Human Gas Exchange System

Distribution of Tissues

Recognising Tissues

Recognising Structures

Structures & Functions of the Gas Exchange System

Gas Exchange Processes

10. Infectious Diseases

Infectious Diseases

Transmission of Disease

Prevention & Control of Disease

Penicillin

Antibiotic Resistance

Consequences of Antibiotic Resistance

11. Immunity

Phagocytes

Antigens

Primary Immune Response

Memory Cells & Immunity

Antibodies

Making Monoclonal Antibodies

Uses of Monoclonal Antibodies

Types of Immunity

How Vaccines Work

Vaccination to Control Disease

12. Energy & Respiration

Energy

ATP

Energy Values of Respiratory Substrates

Respiratory Quotient (RQ)

Investigating RQs

Structure & Function of Mitochondria

The Four Stages in Aerobic Respiration

Aerobic Respiration: Glycolysis

Aerobic Respiration: The Link Reaction

Aerobic Respiration: The Krebs Cycle

Aerobic Respiration: Role of NAD & FAD

Aerobic Respiration: Oxidative Phosphorylation

Anaerobic Respiration

Energy Yield: Aerobic & Anaerobic Respiration

Anaerobic Adaptation of Rice

Aerobic Respiration: Effect of Temperature & Substrate Concentration

13. Photosynthesis

Chloroplasts

Stages of Photosynthesis

Thylakoids & the Stroma

Chloroplast Pigments

Absorption Spectra & Action Spectra

Chromatography of Chloroplast Pigments

Photophosphorylation

The Calvin Cycle

Limiting Factors of Photosynthesis

Investigating the Rate of Photosynthesis

14. Homeostasis

The Control of Blood Glucose

Test Strips & Biosensors

Stomata

Guard Cells

Abscisic Acid & Stomatal Closure

15. Control & Coordination

The Endocrine System

The Nervous System

Neurones

Sensory Receptor Cells

Sequence of Events Resulting in an Action Potential

Transmission of Nerve Impulses

Speed of Conduction of Impulses

The Refractory Period

Cholinergic Synapses

Stimulating Contraction in Striated Muscle

Ultrastructure of Striated Muscle

Sliding Filament Model of Muscular Contraction

Electrical Communication in the Venus Flytrap

The Role of Auxin in Elongation Growth

The Role of Gibberellin in Germination of Barley

16. Inheritance

Haploidy & Diploidy

Homologous Chromosomes

Meiosis in Animal & Plant Cells

Identifying the Stages of Meiosis

Meiosis: Sources of Genetic Variation

Key Terms in Genetics

Predicting Inheritance: Monohybrid Crosses

Predicting Inheritance: Dihybrid Crosses

Predicting Inheritance: Test Crosses

Predicting Inheritance: Chi-squared Test

Genes, Proteins & Phenotype

The Role of Gibberellin in Stem Elongation

Gene Control

Gene Control: Lac Operon

Gene Control: Transcription Factors

17. Selection & Evolution

Variation: Phenotype

Variation: Discontinuous & Continuous

Variation: t-test Method

Variation: t-test Worked Example

Natural Selection

Natural Selection: Types of Selection

Natural Selection: Changes in Allele Frequencies

Natural Selection: Antibiotic Resistance

Natural Selection: Hardy-Weinberg Principle

Artificial Selection

Examples of Artificial Selection

Theory of Evolution

Allopatric & Sympatric Speciation

18. Classification, Biodiversity & Conservation

Definitions of Species

The Three Domains: Archaea, Bacteria & Eukarya

Testing for Distribution & Abundance

Pearson's Linear Correlation

Spearman's Rank Correlation

Simpson's Index

Reasons for Extinction

Reasons for Maintaining Biodiversity

Methods of Conservation

Assisted Reproduction

Controlling Invasive Species

Role of IUCN in Conservation

19. Genetic Technology

Recombinant DNA

Genetic Engineering

Isolating the Desired Gene

Genetic Engineering: Enzymes

Genetic Engineering: Vectors

Genetic Engineering: Promoters & Marker Genes

Gene Editing

Polymerase Chain Reaction

Gel Electrophoresis

Microarrays

Bioinformatics

Recombinant Human Proteins

Genetic Screening

Gene Therapy

Gene Technology in Medicine

Genetically Modified Organisms in Agriculture

Using GMOs in Agriculture

Exam boards

Study tools