BRAINCAKE

AQA AS-level Biology

AQA Biology (7401)14 topics301 lessons

Free AQA AS-level Biology revision for AQA Biology (7401): 14 topics and 301 short lessons, each with R.E.C.I.P.E. recall steps and a quiz. The topics follow the AQA specification.

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1. Biological Molecules

29 lessons

  1. Bonding
  2. Polymers and Macromolecules
  3. Condensation and Hydrolysis
  4. Organic Compounds
  5. Carbohydrates
  6. Monosaccharides
  7. Test for Reducing Sugars
  8. Disaccharides
  9. Test for Non-reducing Sugars
  10. Polysaccharides
  11. Starch
  12. Test for Starch
  13. Glycogen
  14. Cellulose
  15. Roles of Lipids
  16. Triglycerides
  17. Properties of Triglycerides
  18. Phospholipids
  19. Properties of Phospholipids
  20. Test for Lipids
  21. Amino-Acids
  22. Peptide Bond Formation
  23. Primary Structure
  24. Secondary Structure
  25. Tertiary Structure
  26. Quaternary Structure
  27. Test for Proteins
  28. Globular and Fibrous Proteins
  29. Collagen

2. Enzymes

17 lessons

  1. Enzymes
  2. Enzyme Structure
  3. Induced-fit Model
  4. Lock and Key Model
  5. Measuring Enzyme-Catalysed Reactions
  6. Measuring the Rate of Reaction
  7. Effect of Temperature on Enzyme Action
  8. Effect of pH on Enzyme Action
  9. Effect of Enzyme Concentration
  10. Effect of Substrate Concentration
  11. Different Enzymes
  12. Competitive Inhibitors
  13. Non-Competitive Inhibitors
  14. End-Product Inhibition
  15. Exam Style Question 1
  16. Exam Style Question 2
  17. Exam-Style Question 3

3. Nucleic Acids

18 lessons

  1. Nucleotides
  2. RNA
  3. DNA
  4. Complementary Base Pairing
  5. Stability of the Double Helix
  6. Function of DNA
  7. Discovering DNA as the Hereditary Material
  8. DNA Semi-Conservative Replication
  9. Evidence for Semi-Conservative Replication
  10. ATP
  11. ATP Synthesis
  12. Roles of ATP
  13. Water and Hydrogen Bonding
  14. Specific Heat Capacity of Water
  15. Latent heat of Vaporisation of Water
  16. Cohesion and Surface Tension of Water
  17. The Importance of Water
  18. Inorganic Ions

4. Cell Structure

26 lessons

  1. Magnification
  2. Resolution
  3. Cell Fractionation
  4. Ultracentrifugation
  5. Light Microscope
  6. Measuring Cells
  7. Electron Microscope
  8. Transmission Electron Microscope
  9. Scanning Electron Microscope
  10. The Nucleus
  11. Mitochondria
  12. Chloroplasts
  13. Endoplasmic Reticulum
  14. Golgi Apparatus
  15. Lysosomes
  16. Ribosomes
  17. Cell Wall
  18. Vacuoles
  19. Cell Structure and Function
  20. Cell Specialisation
  21. Tissues
  22. Organs
  23. Organ Systems
  24. Prokaryotic Cell Structure
  25. Prokaryotic vs Eukaryotic Cells
  26. Viruses

5. The Cell Cycle

12 lessons

  1. The Cell Cycle
  2. Mitosis
  3. Prophase
  4. Metaphase
  5. Anaphase
  6. Telophase
  7. Cytokinesis
  8. The Importance of Mitosis
  9. Cancer and the Control of Mitosis
  10. Treatment of Cancer
  11. Cell Division in Prokaryotic Cells
  12. The Replication of Viruses

6. Transport Across Cell Membranes

22 lessons

  1. Plasma Membrane
  2. Phospholipids
  3. Proteins
  4. Cholesterol
  5. Glycolipids
  6. Glycoproteins
  7. Fluid-mosaic Model
  8. Membrane Permeability
  9. Simple Diffusion
  10. Facilitated Diffusion
  11. Protein Channels
  12. Carrier Proteins
  13. Water Potential Φ
  14. Osmosis
  15. Osmosis in Animal Cells
  16. Osmosis in Plant Cells
  17. Active Transport
  18. Sodium-Potassium Pump
  19. Increasing the Rate of Movement across a Membrane
  20. Absorption in the Ileum
  21. Co-transport in Absorption
  22. Oral Rehydration Therapy

7. Cell Recognition and the Immune System

30 lessons

  1. The Immune System
  2. Defence Mechanisms
  3. Lymphocytes and Phagocytes
  4. Recognising Self and Non-Self Cells
  5. Phagocytosis
  6. Antigens
  7. Lymphocytes
  8. Cell-Mediated Immunity
  9. Cytotoxic T-cells
  10. Humoral Immunity
  11. Primary and Secondary Immune Response
  12. Antibody Structure
  13. Antibody Function
  14. Monoclonal Antibodies
  15. Drug Delivery and Therapy
  16. Medical Diagnosis
  17. Pregnancy Testing
  18. Ethics
  19. Producing Monoclonal Antibodies
  20. Active, Passive, Natural and Artificial Immunity
  21. Vaccination
  22. Herd Immunity
  23. Vaccination Programme Failure
  24. Ethics
  25. MMR Vaccine Case Study
  26. Structure of HIV Virus
  27. Replication of HIV Virus
  28. AIDS
  29. The ELISA Test
  30. Antibiotics

8. Exchange of Gases

28 lessons

  1. Tissue Fluid
  2. The Need for Specialised Exchange Surfaces
  3. Surface Area to Volume Ratio
  4. The Rate of Diffusion
  5. Features of A Specialised Exchange Surface
  6. Gas Exchange in Unicellular Organisms
  7. Gas Exchange in Insects
  8. Diffusion Gradient
  9. Mass Transport
  10. Increasing the Rate of Diffusion
  11. Limitations of the Tracheal System
  12. Gas Exchange in Fish
  13. Structure of the Gills
  14. Counter Current Exchange
  15. Gas Exchange in Leaves
  16. Stomata
  17. Limiting Water Loss in Insects
  18. Limiting Water Loss in Plants
  19. The Human Gas Exchange System
  20. The Lungs
  21. Mechanism of Breathing
  22. Inspiration
  23. Expiration
  24. Alveoli
  25. Role of Alveoli in Gas Exchange
  26. Correlation and Causation
  27. Risk Factors for Lung Disease
  28. Smoking and Lung Cancer

9. Digestion

10 lessons

  1. Digestion
  2. The Digestive System
  3. Carbohydrate Digestion
  4. Lipid Digestion
  5. Protein Digestion
  6. Structure of the Ileum
  7. Absorption of Amino Acids
  8. Absorption of Monosaccharides
  9. Absorption of Triglycerides
  10. Absorption of Fatty Acids

10. Mass Transport in Animals

27 lessons

  1. Haemoglobin
  2. Loading and Unloading Oxygen
  3. Different Types of Haemoglobin
  4. Oxygen Dissociation Curve
  5. Effect of Carbon Dioxide
  6. Transport of Oxygen
  7. Lugworm
  8. Llama
  9. Fetal Haemoglobin
  10. Myoglobin
  11. The Need for a Transport System
  12. Features of a Transport System
  13. Circulatory Systems
  14. Structure of the Human Heart
  15. Coronary Arteries
  16. Cardiovascular Disease
  17. The Cardiac Cycle
  18. Valves and Control of Blood Flow
  19. Pressure and Volume Changes
  20. Cardiac Output
  21. Blood Vessels
  22. Arteries
  23. Arterioles
  24. Veins and Venules
  25. Capillaries
  26. Tissue Fluid
  27. Return of Tissue Fluid to Blood

11. Mass Transport in Plants

15 lessons

  1. Specialised Plant Cells
  2. Transpiration
  3. Movement of Water into the Root Hair Cells
  4. Movement of Water across the Roots
  5. Movement of Water Up the Stem
  6. Movement of Water Across the Leaf
  7. Movement of Water Through the Stomata
  8. Translocation
  9. Phloem Loading
  10. Mass Flow through Sieve Tube Elements
  11. Mass Flow Model
  12. Phloem Unloading
  13. Ringing Experiments
  14. Tracer Experiments
  15. Evidence for Translocation in Phloem

12. DNA, Genes and Protein Synthesis

15 lessons

  1. Genes
  2. The Genetic Code
  3. Features of the Genetic Code
  4. Chromosomes
  5. Homologous Chromosomes
  6. Alleles
  7. The Human Karyotype
  8. Protein Synthesis
  9. RNA
  10. mRNA
  11. tRNA
  12. Transcription
  13. Splicing pre-mRNA
  14. Translation
  15. Cracking the DNA Code

13. Genetic Diversity

19 lessons

  1. Mutations
  2. Chromosome Mutations
  3. Gene Mutations
  4. Substitution of Bases
  5. Deletion of Bases
  6. Polyploidy and Hybrids
  7. Meiosis
  8. The Process of Meiosis
  9. Genetic Recombination by Crossing Over
  10. Independent Segregation of Chromosomes
  11. Independent Segregation of Chromatids
  12. Number of Chromosome Combinations
  13. Genetic Diversity
  14. Natural Selection
  15. Peppered Moths
  16. Types of Selection
  17. Directional Selection
  18. Antibiotic Resistance
  19. Stabilising Selection

14. Biodiversity

33 lessons

  1. A Species
  2. Binomial System of Naming
  3. Courtship Behaviour
  4. Classification
  5. Taxonomy
  6. Domain
  7. Kingdoms
  8. Phylogeny
  9. Index of Diversity
  10. Example Index of Diversity
  11. Species Diversity and Ecosystems
  12. The Impact of Agriculture
  13. Balancing Conservation and Farming
  14. Managing Ecosystems
  15. Investigating Diversity
  16. Comparing DNA
  17. Comparing mRNA
  18. Comparing Amino-acids Sequences
  19. Sampling
  20. Random Sampling
  21. Normal Distribution
  22. Mean, median and Mode
  23. Mean and Standard Deviation
  24. Interpreting Graphs 1
  25. Interpreting Graphs 2
  26. Interpreting Graphs 3
  27. Interpreting Graphs 4
  28. Interpreting Graphs 5
  29. Interpreting Graphs 6
  30. Interpreting Graphs 7
  31. Interpreting Graphs 8
  32. Interpreting Graphs 9
  33. Interpreting Graphs 10