Source: https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-5-required-practical-light-or-gravity-on-seedlings

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [GCSE](https://senecalearning.com/en-gb/revision-notes/gcse.md) › [Biology](https://senecalearning.com/en-gb/revision-notes/gcse/biology.md) › [AQA](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa.md) › [Higher](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher.md) › Required Practical - Light or Gravity on Seedlings

# Required Practical - Light or Gravity on Seedlings

Biology: AQA GCSE Higher, topic 5.4.5

## Investigating The Effect of Light or Gravity on Seedling Growth

The aim of this experiment is to explore how environmental factors such as light or gravity influence the direction and rate of growth in newly germinated seedlings.

### Apparatus and materials

![Apparatus and materials](https://image-v2.cdn.app.senecalearning.com/2025-10/489448b1-34e1-4134-9f74-770aa5b1172f/9e7c9044-30a8-46a2-a4b6-943848af7462.png)

- 3 Petri dishes
- Cotton wool
- Pipette or dropper
- Ruler (millimetre scale)
- 30 seeds (mustard or cress work well)
- Forceps
- Labels or a marker pen
- Warm, safe place for incubation

### Independent and dependent variables

![Independent and dependent variables](https://image-v2.cdn.app.senecalearning.com/2022-07/f511a4c1-8bb7-41d2-890d-5b721bf70b9a/light-bulb-1867166_1280.jpg)

- Independent variable: 
 - Light conditions (full light, partial light, complete darkness).
- Dependent variable: 
 - Average (mean) height of seedlings after several days.

### Control variables

![Control variables](https://image-v2.cdn.app.senecalearning.com/2022-07/f97f6630-e44d-494d-b41b-96ac79abb642/material1.jpg)

- Control variables:
 - Number of seeds per dish
 - Temperature
 - Volume of water
 - Type and thickness of cotton wool
 - Spacing between seeds

### Method (before germination)

![Method (before germination)](https://image-v2.cdn.app.senecalearning.com/2025-10/55441a1b-a0c7-40a5-a267-b3fa3785faf5/seed.png)

- Line each Petri dish with cotton wool and moisten it using the same volume of water.
- Place the same number of seeds across the surface of each dish.
- Leave the dishes in a warm area where they will not be disturbed.
- Check daily and add more water if the cotton wool begins to dry out.
- When germination begins (after about 2–3 days), make sure each dish contains the same number of healthy seedlings.

### Method (after germination)

![Method (after germination)](https://image-v2.cdn.app.senecalearning.com/2025-10/d13b7df3-5892-4f96-9773-8ef9f92d0d1a/good.png)

- Assign each Petri dish to one of the following conditions:
 - Dish A: Placed in full light.
 - Dish B: Kept in the dark.
 - Dish C: Placed in partial light (a shaded area).
- Over five to seven days, measure the height of every seedling. Write down the results in a table.
- Calculate the mean height for each dish daily.
- Compare the growth patterns to identify how light (or gravity) affects the direction and rate of growth.

### Recording Results

![Recording Results](https://image-v2.cdn.app.senecalearning.com/2025-10/a6aa8c70-516f-426a-a4d4-baeda0a25d00/table-chart-check-list-table-tamplate_142075-8947.jpg)

- Create a results table with columns for each day and condition.
- Draw labelled biological diagrams showing the direction of seedling growth.
- Note differences between the treatments (for example, seedlings in darkness may grow taller but paler as they search for light).

### Results

![Results](https://image-v2.cdn.app.senecalearning.com/2025-10/df355e7d-6289-4336-8768-629a56e765cf/gem.png)

- Light conditions: Seedlings bend towards the light source (positive phototropism).
- Darkness: Seedlings grow taller but weaker and lack chlorophyll.
- Gravity test: Roots grow downward (positive gravitropism), while shoots grow upward (negative gravitropism).

## Test yourself on Required Practical - Light or Gravity on Seedlings

- Which of the following is the dependent variable in this investigation on light's effect on newly germinated seedlings?
- What is the purpose of calculating the mean height of seedlings each day?
- What is correct about investigating the effect of light or gravity on seedling growth?
- How would seedlings in Dish C, placed in partial light, most likely compare with those in Dish A and Dish B?
- Why should extra water be added to the cotton wool if it begins to dry out during the investigation?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/6b76a6e0-cf79-11e7-83a9-29a486db2c9f/section/84a3e782-5ac0-49ee-a15d-ba2338c9493b/session)

- Previous topic: [5.4.4 Effect of Light on Seedlings](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-4-effect-of-light-on-seedlings.md)
- Next topic: [5.4.6 Uses of Plant Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-6-uses-of-plant-hormones.md)

## Biology: AQA GCSE Higher contents

### 1 Cell Biology
- 1.1 What's in Cells?
  - [1.1.1 Types of Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-1-types-of-cells.md)
  - [1.1.2 Properties of Prokaryotes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-2-properties-of-prokaryotes.md)
  - [1.1.3 Orders of Magnitude](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-3-orders-of-magnitude.md)
  - [1.1.4 Standard Form](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-4-standard-form.md)
  - [1.1.5 Standard Form - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-5-standard-form-calculations.md)
  - [1.1.6 Addition in Standard Form - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-6-addition-in-standard-form-calculations.md)
  - [1.1.7 Subtraction in Standard Form - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-7-subtraction-in-standard-form-calculations.md)
  - [1.1.8 Multiplication in Standard Form - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-8-multiplication-in-standard-form-calculations.md)
  - [1.1.9 Division in Standard Form - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-9-division-in-standard-form-calculations.md)
  - [1.1.10 Animal Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-10-animal-cells.md)
  - [1.1.11 Plant Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-11-plant-cells.md)
  - [1.1.12 Differentiation in Plants & Animals](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-12-differentiation-in-plants-and-animals.md)
  - [1.1.13 Bacterial Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-13-bacterial-cells.md)
  - [1.1.14 Types of Cells HyperLearning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-14-types-of-cells-hyperlearning.md)
  - [1.1.15 Cell Specialisation in Animals](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-15-cell-specialisation-in-animals.md)
  - [1.1.16 Sperm Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-16-sperm-cells.md)
  - [1.1.17 Nerve Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-17-nerve-cells.md)
  - [1.1.18 Muscle Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-18-muscle-cells.md)
  - [1.1.19 Cell Specialisation in Plants - Root Hair Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-19-cell-specialisation-in-plants-root-hair-cells.md)
  - [1.1.20 Cell Specialisation in Plants - Xylem](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-20-cell-specialisation-in-plants-xylem.md)
  - [1.1.21 Cell Specialisation in Plants - Phloem](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-21-cell-specialisation-in-plants-phloem.md)
  - [1.1.22 Microscopy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-22-microscopy.md)
  - [1.1.23 Magnification](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-23-magnification.md)
  - [1.1.24 Developments in Microscopy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-24-developments-in-microscopy.md)
  - [1.1.25 Required Practical - Microscopy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-25-required-practical-microscopy.md)
  - [1.1.26 Microscopy - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-26-microscopy-calculations.md)
  - [1.1.27 Culturing Microorganisms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-27-culturing-microorganisms.md)
  - [1.1.28 Contamination](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-28-contamination.md)
  - [1.1.29 Avoiding Contamination](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-29-avoiding-contamination.md)
  - [1.1.30 Calculating Bacteria](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-30-calculating-bacteria.md)
  - [1.1.31 Calculating Bacteria - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-31-calculating-bacteria-calculations.md)
  - [1.1.32 Required Practical - Bacteria](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-32-required-practical-bacteria.md)
  - [1.1.33 Exam-Style Questions - Cell Structure & Microscopy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-33-exam-style-questions-cell-structure-and-microscopy.md)
  - [1.1.34 Diagnostic Misconceptions - Converting](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-34-diagnostic-misconceptions-converting.md)
  - [1.1.35 Diagnostic Misconceptions - Animal Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-35-diagnostic-misconceptions-animal-cells.md)
  - [1.1.36 Diagnostic Misconceptions - Mitochondria](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-36-diagnostic-misconceptions-mitochondria.md)
  - [1.1.37 End of Topic Test - What's in Cells?](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-1-37-end-of-topic-test-whats-in-cells.md)
- 1.2 Cell Division
  - [1.2.1 Chromosomes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-1-chromosomes.md)
  - [1.2.2 The Cell Cycle](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-2-the-cell-cycle.md)
  - [1.2.3 Mitosis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-3-mitosis.md)
  - [1.2.4 Stem Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-4-stem-cells.md)
  - [1.2.5 Use of Stem Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-5-use-of-stem-cells.md)
  - [1.2.6 Disadvantages of Stem Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-6-disadvantages-of-stem-cells.md)
  - [1.2.7 Exam-Style Questions - Mitosis & Cell Cycle](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-7-exam-style-questions-mitosis-and-cell-cycle.md)
  - [1.2.8 Diagnostic Misconceptions - Mitosis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-2-8-diagnostic-misconceptions-mitosis.md)
- 1.3 Transport in Cells
  - [1.3.1 Diffusion](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-1-diffusion.md)
  - [1.3.2 Factors Affecting Diffusion](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-2-factors-affecting-diffusion.md)
  - [1.3.3 Surface Area : Volume](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-3-surface-area-volume.md)
  - [1.3.4 Surface Area : Volume - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-4-surface-area-volume-calculations.md)
  - [1.3.5 Exchange Surfaces](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-5-exchange-surfaces.md)
  - [1.3.6 Examples of Exchange Surfaces](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-6-examples-of-exchange-surfaces.md)
  - [1.3.7 Osmosis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-7-osmosis.md)
  - [1.3.8 Osmosis 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-8-osmosis-2.md)
  - [1.3.9 Required Practical - Osmosis in Plant Tissue](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-9-required-practical-osmosis-in-plant-tissue.md)
  - [1.3.10 Active Transport](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-10-active-transport.md)
  - [1.3.11 Transport in Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-11-transport-in-cells.md)
  - [1.3.12 Grade 9 - Cell Transport](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-12-grade-9-cell-transport.md)
  - [1.3.13 Diagnostic Misconceptions - Water Moving](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-13-diagnostic-misconceptions-water-moving.md)
  - [1.3.14 Diagnostic Misconceptions - Active Transport](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-14-diagnostic-misconceptions-active-transport.md)
  - [1.3.15 End of Topic Test - Cell Division & Transport](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/1-3-15-end-of-topic-test-cell-division-and-transport.md)

### 2 Organisation
- 2.1 Principles of Organisation
  - [2.1.1 Cells & Tissues](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-1-1-cells-and-tissues.md)
  - [2.1.2 Organs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-1-2-organs.md)
  - [2.1.3 Organ Systems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-1-3-organ-systems.md)
  - [2.1.4 Organisms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-1-4-organisms.md)
- 2.2 Enzymes
  - [2.2.1 Enzymes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-1-enzymes.md)
  - [2.2.2 Enzymes HyperFlashcards](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-2-enzymes-hyperflashcards.md)
  - [2.2.3 Rate of Reaction](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-3-rate-of-reaction.md)
  - [2.2.4 Calculating Rate of Reaction](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-4-calculating-rate-of-reaction.md)
  - [2.2.5 Rate of Reaction - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-5-rate-of-reaction-calculations.md)
  - [2.2.6 Digestion](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-6-digestion.md)
  - [2.2.7 Bile](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-7-bile.md)
  - [2.2.8 Examples of Digestive Enzymes - Amylase](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-8-examples-of-digestive-enzymes-amylase.md)
  - [2.2.9 Examples of Digestive Enzymes - Protease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-9-examples-of-digestive-enzymes-protease.md)
  - [2.2.10 Examples of Digestive Enzymes - Lipase](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-10-examples-of-digestive-enzymes-lipase.md)
  - [2.2.11 Testing for Biological Molecules](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-11-testing-for-biological-molecules.md)
  - [2.2.12 Required Practical - Testing for Food Chemicals](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-12-required-practical-testing-for-food-chemicals.md)
  - [2.2.13 Required Practical - Enzymes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-13-required-practical-enzymes.md)
  - [2.2.14 Grade 9 - Enzymes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-14-grade-9-enzymes.md)
  - [2.2.15 Exam-Style Questions - Enzymes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-15-exam-style-questions-enzymes.md)
  - [2.2.16 Diagnostic Misconceptions - High Temperatures](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-16-diagnostic-misconceptions-high-temperatures.md)
  - [2.2.17 Diagnostic Misconceptions - Low Temperatures](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-17-diagnostic-misconceptions-low-temperatures.md)
  - [2.2.18 Diagnostic Misconceptions - Stomach Acid](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-18-diagnostic-misconceptions-stomach-acid.md)
  - [2.2.19 Diagnostic Misconceptions - Substrate Shape](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-19-diagnostic-misconceptions-substrate-shape.md)
  - [2.2.20 End of Topic Test - Organisation & Enzymes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-2-20-end-of-topic-test-organisation-and-enzymes.md)
- 2.3 Circulatory System
  - [2.3.1 Types of Blood Vessels](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-1-types-of-blood-vessels.md)
  - [2.3.2 Blood Vessels - Arteries](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-2-blood-vessels-arteries.md)
  - [2.3.3 Blood Vessels - Capillaries](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-3-blood-vessels-capillaries.md)
  - [2.3.4 Blood Vessels - Veins](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-4-blood-vessels-veins.md)
  - [2.3.5 The Heart - Structure](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-5-the-heart-structure.md)
  - [2.3.6 The Heart - Function](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-6-the-heart-function.md)
  - [2.3.7 Important Blood Vessels](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-7-important-blood-vessels.md)
  - [2.3.8 Double Circulatory System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-8-double-circulatory-system.md)
  - [2.3.9 Gas Exchange](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-9-gas-exchange.md)
  - [2.3.10 Gas Exchange - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-10-gas-exchange-calculations.md)
  - [2.3.11 Alveoli](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-11-alveoli.md)
  - [2.3.12 Blood Components](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-12-blood-components.md)
  - [2.3.13 Platelets](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-13-platelets.md)
  - [2.3.14 Red Blood Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-14-red-blood-cells.md)
  - [2.3.15 White Blood Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-15-white-blood-cells.md)
  - [2.3.16 End of Topic Test - Circulatory System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-3-16-end-of-topic-test-circulatory-system.md)
- 2.4 Non-Communicable Diseases
  - [2.4.1 Health Issues](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-1-health-issues.md)
  - [2.4.2 Disease Interactions](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-2-disease-interactions.md)
  - [2.4.3 Sampling](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-3-sampling.md)
  - [2.4.4 Sampling - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-4-sampling-calculations.md)
  - [2.4.5 Risk Factors](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-5-risk-factors.md)
  - [2.4.6 Examples of Risk Factors](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-6-examples-of-risk-factors.md)
  - [2.4.7 Risk Factor Graphs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-7-risk-factor-graphs.md)
  - [2.4.8 Coronary Heart Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-8-coronary-heart-disease.md)
  - [2.4.9 Heart Valve Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-9-heart-valve-disease.md)
  - [2.4.10 Heart Failure](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-10-heart-failure.md)
  - [2.4.11 Treating Heart Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-11-treating-heart-disease.md)
  - [2.4.12 Comparing Treatments of Heart Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-12-comparing-treatments-of-heart-disease.md)
  - [2.4.13 Cancer](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-13-cancer.md)
  - [2.4.14 Cancer Risk Factors](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-14-cancer-risk-factors.md)
  - [2.4.15 End of Topic Test - Non-Communicable Diseases](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-15-end-of-topic-test-non-communicable-diseases.md)
  - [2.4.16 Exam-Style Questions - Coronary Heart Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-4-16-exam-style-questions-coronary-heart-disease.md)
- 2.5 Plant Tissues, Organs & Systems
  - [2.5.1 Plant Organs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-1-plant-organs.md)
  - [2.5.2 Leaves](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-2-leaves.md)
  - [2.5.3 Transpiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-3-transpiration.md)
  - [2.5.4 Rate of Transpiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-4-rate-of-transpiration.md)
  - [2.5.5 Measuring Transpiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-5-measuring-transpiration.md)
  - [2.5.6 Translocation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-6-translocation.md)
  - [2.5.7 Transpiration Tissues - Xylem Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-7-transpiration-tissues-xylem-cells.md)
  - [2.5.8 Transpiration Tissues - Root Hair Cells](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-8-transpiration-tissues-root-hair-cells.md)
  - [2.5.9 Stomata](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-9-stomata.md)
  - [2.5.10 States of Stomata](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-10-states-of-stomata.md)
  - [2.5.11 Premium Knowledge - Transpiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-11-premium-knowledge-transpiration.md)
  - [2.5.12 End of Topic Test - Plants](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-12-end-of-topic-test-plants.md)
  - [2.5.13 Exam-Style Questions - Plant Tissues](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-13-exam-style-questions-plant-tissues.md)
  - [2.5.14 Diagnostic Misconceptions - Plant Food](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-14-diagnostic-misconceptions-plant-food.md)
  - [2.5.15 Diagnostic Misconceptions - Plants & Water](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-15-diagnostic-misconceptions-plants-and-water.md)
  - [2.5.16 Diagnostic Misconceptions - Plants Don't Breathe](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/2-5-16-diagnostic-misconceptions-plants-dont-breathe.md)

### 3 Infection & Response
- 3.1 Communicable Disease
  - [3.1.1 Spreading Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-1-spreading-disease.md)
  - [3.1.2 Causing Diseases](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-2-causing-diseases.md)
  - [3.1.3 Preventing Infection](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-3-preventing-infection.md)
  - [3.1.4 Communicable Disease - Viruses](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-4-communicable-disease-viruses.md)
  - [3.1.5 Examples of Viruses](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-5-examples-of-viruses.md)
  - [3.1.6 Communicable Disease - Bacteria](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-6-communicable-disease-bacteria.md)
  - [3.1.7 Communicable Disease - Fungi](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-7-communicable-disease-fungi.md)
  - [3.1.8 Communicable Disease - Protists](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-8-communicable-disease-protists.md)
  - [3.1.9 Human Defence Systems - Non-Specific Defences](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-9-human-defence-systems-non-specific-defences.md)
  - [3.1.10 Human Defence Systems - Immune Systems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-10-human-defence-systems-immune-systems.md)
  - [3.1.11 Antibodies](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-11-antibodies.md)
  - [3.1.12 Vaccinations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-12-vaccinations.md)
  - [3.1.13 The Immune System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-13-the-immune-system.md)
  - [3.1.14 The Immune System 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-14-the-immune-system-2.md)
  - [3.1.15 Antibiotics](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-15-antibiotics.md)
  - [3.1.16 Antibiotic Resistance](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-16-antibiotic-resistance.md)
  - [3.1.17 Antibiotic Resistance 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-17-antibiotic-resistance-2.md)
  - [3.1.18 Drug Discovery](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-18-drug-discovery.md)
  - [3.1.19 Developing New Drugs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-19-developing-new-drugs.md)
  - [3.1.20 Drug Testing](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-20-drug-testing.md)
  - [3.1.21 Drug Testing in Laboratories](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-21-drug-testing-in-laboratories.md)
  - [3.1.22 Double-Blind Trials](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-22-double-blind-trials.md)
  - [3.1.23 Drug Testing / Efficacy - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-23-drug-testing-efficacy-calculations.md)
  - [3.1.24 End of Topic Test - Communicable Diseases](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-24-end-of-topic-test-communicable-diseases.md)
  - [3.1.25 Exam-Style Questions - Microorganisms & Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-25-exam-style-questions-microorganisms-and-disease.md)
  - [3.1.26 Diagnostic Misconceptions - Antibiotics](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-1-26-diagnostic-misconceptions-antibiotics.md)
- 3.2 Monoclonal Antibodies
  - [3.2.1 Monoclonal Antibodies](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-2-1-monoclonal-antibodies.md)
  - [3.2.2 Producing Monoclonal Antibodies](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-2-2-producing-monoclonal-antibodies.md)
  - [3.2.3 Uses of Monoclonal Antibodies](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-2-3-uses-of-monoclonal-antibodies.md)
  - [3.2.4 Grade 9 - Monoclonal Antibodies](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-2-4-grade-9-monoclonal-antibodies.md)
- 3.3 Plant Diseases
  - [3.3.1 Ion Deficiencies in Plants](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-1-ion-deficiencies-in-plants.md)
  - [3.3.2 Plant Defences](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-2-plant-defences.md)
  - [3.3.3 Signs of Plant Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-3-signs-of-plant-disease.md)
  - [3.3.4 Identifying Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-4-identifying-disease.md)
  - [3.3.5 Other Plant Diseases](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-5-other-plant-diseases.md)
  - [3.3.6 End of Topic Test - Antibodies & Plant Disease](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/3-3-6-end-of-topic-test-antibodies-and-plant-disease.md)

### 4 Bioenergetics
- 4.1 Photosynthesis
  - [4.1.1 Photosynthesis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-1-photosynthesis.md)
  - [4.1.2 Photosynthesis Equation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-2-photosynthesis-equation.md)
  - [4.1.3 Rate of Photosynthesis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-3-rate-of-photosynthesis.md)
  - [4.1.4 Limiting Factors](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-4-limiting-factors.md)
  - [4.1.5 Photosynthesis in Farming](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-5-photosynthesis-in-farming.md)
  - [4.1.6 Uses of Glucose](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-6-uses-of-glucose.md)
  - [4.1.7 Photosynthesis - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-7-photosynthesis-calculations.md)
  - [4.1.8 Required Practical - Light Intensity](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-8-required-practical-light-intensity.md)
  - [4.1.9 Grade 9 - Photosynthesis Experiment](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-9-grade-9-photosynthesis-experiment.md)
  - [4.1.10 Exam-Style Questions - Rate of Photosynthesis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-10-exam-style-questions-rate-of-photosynthesis.md)
  - [4.1.11 Diagnostic Misconceptions - Photosynthesis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-11-diagnostic-misconceptions-photosynthesis.md)
  - [4.1.12 Diagnostic Misconceptions - Plants Respiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-1-12-diagnostic-misconceptions-plants-respiration.md)
- 4.2 Respiration
  - [4.2.1 Organisms and Energy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-1-organisms-and-energy.md)
  - [4.2.2 Respiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-2-respiration.md)
  - [4.2.3 Metabolism](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-3-metabolism.md)
  - [4.2.4 Respiration - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-4-respiration-calculations.md)
  - [4.2.5 Respiration During Exercise](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-5-respiration-during-exercise.md)
  - [4.2.6 Oxygen Debt](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-6-oxygen-debt.md)
  - [4.2.7 Respiration HyperLearning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-7-respiration-hyperlearning.md)
  - [4.2.8 End of Topic Test - Photosynthesis and Respiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-8-end-of-topic-test-photosynthesis-and-respiration.md)
  - [4.2.9 Exam-Style Questions - Anaerobic Respiration](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/4-2-9-exam-style-questions-anaerobic-respiration.md)

### 5 Homeostasis & Response
- 5.1 Homeostasis
  - [5.1.1 Homeostasis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-1-1-homeostasis.md)
  - [5.1.2 Regulating Internal Conditions](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-1-2-regulating-internal-conditions.md)
  - [5.1.3 Homeostasis & Negative Feedback](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-1-3-homeostasis-and-negative-feedback.md)
  - [5.1.4 The Body's Negative Feedback Loop](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-1-4-the-bodys-negative-feedback-loop.md)
  - [5.1.5 Exam-Style Questions - Exercise & Homeostasis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-1-5-exam-style-questions-exercise-and-homeostasis.md)
- 5.2 The Human Nervous System
  - [5.2.1 The Nervous System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-1-the-nervous-system.md)
  - [5.2.2 The Nervous System HyperFlashcards](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-2-the-nervous-system-hyperflashcards.md)
  - [5.2.3 Synapses](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-3-synapses.md)
  - [5.2.4 Reflexes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-4-reflexes.md)
  - [5.2.5 Components of a Reflex Arc](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-5-components-of-a-reflex-arc.md)
  - [5.2.6 Required Practical - Human Reaction Times](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-6-required-practical-human-reaction-times.md)
  - [5.2.7 The Brain](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-7-the-brain.md)
  - [5.2.8 Parts of the Brain](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-8-parts-of-the-brain.md)
  - [5.2.9 The Brain: Neuro Techniques](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-9-the-brain-neuro-techniques.md)
  - [5.2.10 Retina Scanning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-10-retina-scanning.md)
  - [5.2.11 Eye Anatomy](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-11-eye-anatomy.md)
  - [5.2.12 Eye Function - Focus](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-12-eye-function-focus.md)
  - [5.2.13 Eye Function - Light](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-13-eye-function-light.md)
  - [5.2.14 Eye Defects](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-14-eye-defects.md)
  - [5.2.15 Thermoregulation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-15-thermoregulation.md)
  - [5.2.16 Hot & Cold](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-16-hot-and-cold.md)
  - [5.2.17 Thermoregulation - Sweating & Shivering](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-17-thermoregulation-sweating-and-shivering.md)
  - [5.2.18 Thermoregulation - Body Hair](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-18-thermoregulation-body-hair.md)
  - [5.2.19 Thermoregulation - Blood Vessels](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-19-thermoregulation-blood-vessels.md)
  - [5.2.20 Body Temperature HyperLearning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-20-body-temperature-hyperlearning.md)
  - [5.2.21 End of Topic Test - Human Nervous System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-21-end-of-topic-test-human-nervous-system.md)
  - [5.2.22 Exam-Style Questions - Nervous System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-22-exam-style-questions-nervous-system.md)
  - [5.2.23 Diagnostic Misconceptions - Nervous System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-2-23-diagnostic-misconceptions-nervous-system.md)
- 5.3 Hormonal Coordination in Humans
  - [5.3.1 Endocrine Glands](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-1-endocrine-glands.md)
  - [5.3.2 The Endocrine System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-2-the-endocrine-system.md)
  - [5.3.3 Thyroxine](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-3-thyroxine.md)
  - [5.3.4 Adrenaline](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-4-adrenaline.md)
  - [5.3.5 Blood Glucose](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-5-blood-glucose.md)
  - [5.3.6 Detecting Glucose](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-6-detecting-glucose.md)
  - [5.3.7 Diabetes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-7-diabetes.md)
  - [5.3.8 Type 1 Diabetes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-8-type-1-diabetes.md)
  - [5.3.9 Type 2 Diabetes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-9-type-2-diabetes.md)
  - [5.3.10 Water Balance](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-10-water-balance.md)
  - [5.3.11 Kidneys](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-11-kidneys.md)
  - [5.3.12 Urea](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-12-urea.md)
  - [5.3.13 Urine Production](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-13-urine-production.md)
  - [5.3.14 Urine](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-14-urine.md)
  - [5.3.15 Dialysis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-15-dialysis.md)
  - [5.3.16 Dialysis - Pros & Cons](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-16-dialysis-pros-and-cons.md)
  - [5.3.17 Transplants](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-17-transplants.md)
  - [5.3.18 Transplants - Pros & Cons](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-18-transplants-pros-and-cons.md)
  - [5.3.19 Puberty](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-19-puberty.md)
  - [5.3.20 Menstruation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-20-menstruation.md)
  - [5.3.21 Menstrual Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-21-menstrual-hormones.md)
  - [5.3.22 Menstrual Cycle](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-22-menstrual-cycle.md)
  - [5.3.23 Contraception - 'Natural Methods'](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-23-contraception-natural-methods.md)
  - [5.3.24 Contraception - Sterilisation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-24-contraception-sterilisation.md)
  - [5.3.25 Contraception - Condoms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-25-contraception-condoms.md)
  - [5.3.26 Contraception - The Pill](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-26-contraception-the-pill.md)
  - [5.3.27 Contraception - Diaphragm & IUDs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-27-contraception-diaphragm-and-iuds.md)
  - [5.3.28 Contraception - Other Options](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-28-contraception-other-options.md)
  - [5.3.29 Hormones for Infertility](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-29-hormones-for-infertility.md)
  - [5.3.30 In Vitro Fertilisation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-30-in-vitro-fertilisation.md)
  - [5.3.31 Fertility Treatments - Pros & Cons](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-31-fertility-treatments-pros-and-cons.md)
  - [5.3.32 End of Topic Test - Homeostasis & Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-32-end-of-topic-test-homeostasis-and-hormones.md)
  - [5.3.33 Grade 9 - Hormonal Coordination](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-33-grade-9-hormonal-coordination.md)
  - [5.3.34 Exam-Style Questions - Hormones & Contraception](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-3-34-exam-style-questions-hormones-and-contraception.md)
- 5.4 Plant Hormones
  - [5.4.1 Plant Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-1-plant-hormones.md)
  - [5.4.2 Types of Tropisms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-2-types-of-tropisms.md)
  - [5.4.3 Auxins & Tropisms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-3-auxins-and-tropisms.md)
  - [5.4.4 Effect of Light on Seedlings](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-4-effect-of-light-on-seedlings.md)
  - [5.4.5 Required Practical - Light or Gravity on Seedlings](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-5-required-practical-light-or-gravity-on-seedlings.md)
  - [5.4.6 Uses of Plant Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-6-uses-of-plant-hormones.md)
  - [5.4.7 End of Topic Test - Hormones](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/5-4-7-end-of-topic-test-hormones.md)

### 6 Inheritance, Variation & Evolution
- 6.1 Reproduction
  - [6.1.1 Cell Division](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-1-cell-division.md)
  - [6.1.2 Meiosis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-2-meiosis.md)
  - [6.1.3 Sexual Reproduction](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-3-sexual-reproduction.md)
  - [6.1.4 Asexual Reproduction](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-4-asexual-reproduction.md)
  - [6.1.5 Sexual Reproduction Advantages](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-5-sexual-reproduction-advantages.md)
  - [6.1.6 Asexual Reproduction Advantages](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-6-asexual-reproduction-advantages.md)
  - [6.1.7 Genome](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-7-genome.md)
  - [6.1.8 Genome - Diagram](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-8-genome-diagram.md)
  - [6.1.9 Genome Sequencing](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-9-genome-sequencing.md)
  - [6.1.10 Nucleotide](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-10-nucleotide.md)
  - [6.1.11 DNA Structure](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-11-dna-structure.md)
  - [6.1.12 Protein Synthesis](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-12-protein-synthesis.md)
  - [6.1.13 Protein Synthesis 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-13-protein-synthesis-2.md)
  - [6.1.14 Mutations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-14-mutations.md)
  - [6.1.15 Alleles](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-15-alleles.md)
  - [6.1.16 Genotype vs Phenotype](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-16-genotype-vs-phenotype.md)
  - [6.1.17 Punnett Squares](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-17-punnett-squares.md)
  - [6.1.18 Punnett Squares 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-18-punnett-squares-2.md)
  - [6.1.19 Inherited Disorders](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-19-inherited-disorders.md)
  - [6.1.20 Cystic Fibrosis Punnett Square](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-20-cystic-fibrosis-punnett-square.md)
  - [6.1.21 Family Trees](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-21-family-trees.md)
  - [6.1.22 Polydactyly](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-22-polydactyly.md)
  - [6.1.23 Genetic Crosses - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-23-genetic-crosses-calculations.md)
  - [6.1.24 Genome Screening](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-24-genome-screening.md)
  - [6.1.25 Disadvantages of Embryonic Screening](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-25-disadvantages-of-embryonic-screening.md)
  - [6.1.26 Sex Determination](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-26-sex-determination.md)
  - [6.1.27 End of Topic Test - Reproduction](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-27-end-of-topic-test-reproduction.md)
  - [6.1.28 Exam-Style Questions - DNA & Genetics](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-28-exam-style-questions-dna-and-genetics.md)
  - [6.1.29 Diagnostic Misconceptions - Mutations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-29-diagnostic-misconceptions-mutations.md)
  - [6.1.30 Diagnostic Misconceptions - Chromosomes](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-30-diagnostic-misconceptions-chromosomes.md)
  - [6.1.31 Diagnostic Misconceptions - Genes & Alleles](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-1-31-diagnostic-misconceptions-genes-and-alleles.md)
- 6.2 Variation & Evolution
  - [6.2.1 Variation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-1-variation.md)
  - [6.2.2 Evolution & Speciation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-2-evolution-and-speciation.md)
  - [6.2.3 Natural Selection](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-3-natural-selection.md)
  - [6.2.4 Selective Breeding](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-4-selective-breeding.md)
  - [6.2.5 Selective Breeding 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-5-selective-breeding-2.md)
  - [6.2.6 Uses of Selective Breeding](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-6-uses-of-selective-breeding.md)
  - [6.2.7 Dangers of Selective Breeding](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-7-dangers-of-selective-breeding.md)
  - [6.2.8 Genetic Engineering](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-8-genetic-engineering.md)
  - [6.2.9 Genetic Engineering 2](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-9-genetic-engineering-2.md)
  - [6.2.10 Uses of Genetic Modification](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-10-uses-of-genetic-modification.md)
  - [6.2.11 Advantages of Genetic Modification](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-11-advantages-of-genetic-modification.md)
  - [6.2.12 Disadvantages of Genetic Modification](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-12-disadvantages-of-genetic-modification.md)
  - [6.2.13 Cloning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-13-cloning.md)
  - [6.2.14 Cloning Plants](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-14-cloning-plants.md)
  - [6.2.15 Cloning Animals](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-15-cloning-animals.md)
  - [6.2.16 Adult Cell Cloning](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-16-adult-cell-cloning.md)
  - [6.2.17 End of Topic Test - Variation & Evolution](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-17-end-of-topic-test-variation-and-evolution.md)
  - [6.2.18 Exam-Style Questions - Selective Breeding](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-2-18-exam-style-questions-selective-breeding.md)
- 6.3 Genetics & Evolution
  - [6.3.1 Natural Selection](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-1-natural-selection.md)
  - [6.3.2 Controversy Around Natural Selection](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-2-controversy-around-natural-selection.md)
  - [6.3.3 Darwin's Theory of Evolution](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-3-darwins-theory-of-evolution.md)
  - [6.3.4 Inheritance Theory](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-4-inheritance-theory.md)
  - [6.3.5 Speciation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-5-speciation.md)
  - [6.3.6 Alfred Russel Wallace](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-6-alfred-russel-wallace.md)
  - [6.3.7 Evidence for Evolution](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-7-evidence-for-evolution.md)
  - [6.3.8 Fossils](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-8-fossils.md)
  - [6.3.9 Resistant Bacteria](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-9-resistant-bacteria.md)
  - [6.3.10 Genetics](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-10-genetics.md)
  - [6.3.11 Extinctions](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-11-extinctions.md)
  - [6.3.12 Grade 9 - Evolution](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-12-grade-9-evolution.md)
  - [6.3.13 Diagnostic Misconceptions - Natural Selection](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-3-13-diagnostic-misconceptions-natural-selection.md)
- 6.4 Classification
  - [6.4.1 Classification of Living Organisms](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-4-1-classification-of-living-organisms.md)
  - [6.4.2 Traditional System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-4-2-traditional-system.md)
  - [6.4.3 Classification of Living Organisms: Updated System](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-4-3-classification-of-living-organisms-updated-system.md)
  - [6.4.4 Evolutionary Trees](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-4-4-evolutionary-trees.md)
  - [6.4.5 End of Topic Test - Genetics & Classification](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/6-4-5-end-of-topic-test-genetics-and-classification.md)

### 7 Ecology
- 7.1 Adaptations & Interdependence
  - [7.1.1 Communities: Ecosystems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-1-1-communities-ecosystems.md)
  - [7.1.2 Communities: Resources](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-1-2-communities-resources.md)
  - [7.1.3 Species Interdependence](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-1-3-species-interdependence.md)
  - [7.1.4 Stable Communities](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-1-4-stable-communities.md)
- 7.2 Organisation of Ecosystems
  - [7.2.1 Population Dynamics](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-1-population-dynamics.md)
  - [7.2.2 Predator-Prey Graphs](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-2-predator-prey-graphs.md)
  - [7.2.3 Impact of Environmental Change](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-3-impact-of-environmental-change.md)
  - [7.2.4 Causes of Environmental Change](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-4-causes-of-environmental-change.md)
  - [7.2.5 Assessing Ecosystems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-5-assessing-ecosystems.md)
  - [7.2.6 Organism Abundance](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-6-organism-abundance.md)
  - [7.2.7 Required Practical - Population Size](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-7-required-practical-population-size.md)
  - [7.2.8 Assessing Ecosystems - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-8-assessing-ecosystems-calculations.md)
  - [7.2.9 The Carbon Cycle](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-9-the-carbon-cycle.md)
  - [7.2.10 The Water Cycle](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-10-the-water-cycle.md)
  - [7.2.11 The Cycling of Materials](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-11-the-cycling-of-materials.md)
  - [7.2.12 Decay](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-12-decay.md)
  - [7.2.13 Anaerobic Decay](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-13-anaerobic-decay.md)
  - [7.2.14 Biogas Generators](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-14-biogas-generators.md)
  - [7.2.15 Required Practical - Decay](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-15-required-practical-decay.md)
  - [7.2.16 End of Topic Test - Organisation of Ecosystems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-16-end-of-topic-test-organisation-of-ecosystems.md)
  - [7.2.17 Grade 9 - Ecosystems](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-17-grade-9-ecosystems.md)
  - [7.2.18 Exam-Style Questions - Decomposition](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-2-18-exam-style-questions-decomposition.md)
- 7.3 Biodiversity
  - [7.3.1 Humans & Biodiversity](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-1-humans-and-biodiversity.md)
  - [7.3.2 Waste Management](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-2-waste-management.md)
  - [7.3.3 Human Activities](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-3-human-activities.md)
  - [7.3.4 Land Use](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-4-land-use.md)
  - [7.3.5 Deforestation](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-5-deforestation.md)
  - [7.3.6 Carbon Dioxide](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-6-carbon-dioxide.md)
  - [7.3.7 The Greenhouse Effect](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-7-the-greenhouse-effect.md)
  - [7.3.8 Global Warming](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-8-global-warming.md)
  - [7.3.9 Maintaining Biodiversity](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-9-maintaining-biodiversity.md)
  - [7.3.10 End of Topic Test - Adaptations & Biodiversity](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-3-10-end-of-topic-test-adaptations-and-biodiversity.md)
- 7.4 Trophic Levels
  - [7.4.1 Trophic Levels](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-1-trophic-levels.md)
  - [7.4.2 Trophic Levels: Food Chains](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-2-trophic-levels-food-chains.md)
  - [7.4.3 Trophic Levels: Decomposers](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-3-trophic-levels-decomposers.md)
  - [7.4.4 Pyramids of Biomass](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-4-pyramids-of-biomass.md)
  - [7.4.5 Transfer Efficiency](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-5-transfer-efficiency.md)
  - [7.4.6 Reasons for Energy Wastage](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-6-reasons-for-energy-wastage.md)
  - [7.4.7 Transfer Efficiency - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-7-transfer-efficiency-calculations.md)
  - [7.4.8 Premium Knowledge - Trophic Levels & Food Chains](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-8-premium-knowledge-trophic-levels-and-food-chains.md)
  - [7.4.9 Exam-Style Questions - Food Chains](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-9-exam-style-questions-food-chains.md)
  - [7.4.10 Diagnostic Misconceptions - Arrows](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-4-10-diagnostic-misconceptions-arrows.md)
- 7.5 Food Production
  - [7.5.1 Food Security](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-1-food-security.md)
  - [7.5.2 Food Production: Biotechnology](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-2-food-production-biotechnology.md)
  - [7.5.3 Declining Fish Stock](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-3-declining-fish-stock.md)
  - [7.5.4 Sustainable Fishing](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-4-sustainable-fishing.md)
  - [7.5.5 Farming](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-5-farming.md)
  - [7.5.6 Food Production - Calculations](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-6-food-production-calculations.md)
  - [7.5.7 End of Topic Test - Food & Trophic Levels](https://senecalearning.com/en-gb/revision-notes/gcse/biology/aqa/higher/7-5-7-end-of-topic-test-food-and-trophic-levels.md)