Source: https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-4-active-transport

[Revision notes](https://senecalearning.com/en-gb/revision-notes.md) › [BTEC](https://senecalearning.com/en-gb/revision-notes/btec.md) › [Science](https://senecalearning.com/en-gb/revision-notes/btec/science.md) › [Applied Science: BTEC Level 3](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3.md) › Active Transport

# Active Transport

Applied Science: BTEC Level 3 National Extended Diploma, topic 4.8.4

## Active Transport in Humans and Plants

Active transport uses energy and is in charge of moving ions and molecules across a membrane against the concentration gradient.

### Carrier proteins

![Carrier proteins](https://image-v2.cdn.app.senecalearning.com/2018-09/bff5ee02-da00-4d84-82fd-1ccf8a18a3d0/channel-carrier-protein-transport-.jpg)

- An important membrane adaptation for active transport is the presence of specific carrier proteins to facilitate movement.

### Sugar absorption in the gut

![Sugar absorption in the gut](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.2%20Osmosis/sugar-258113_640-min.jpg)

- One example of active transport is sugar absorption in the gut.
 - Active transport allows sugar molecules, which are needed for cell respiration, to be absorbed into the blood from the gut, even when the sugar concentration of the blood is higher.

### Mineral absorption in plants

![Mineral absorption in plants](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.1%20Diffusion%20and%20active%20transport/pexels-photo-315696-min.jpg)

- Another example of active transport is mineral absorption in plants.
 - Active transport in the root hairs of plants allows plants to absorb mineral ions, which are necessary for healthy growth, even though the concentration of minerals is usually lower in the soil than in the root hair.

### Rate of active transport

![Rate of active transport](https://image-v2.cdn.app.senecalearning.com/2018-09/b90aada5-5250-4779-aaec-d549a4c28cec/Fluid-Mosaic-Model-cell-surface-plasma-membrane-.png)

- The main factors that affect the rate of active transport are:
 - The surface area of cell membranes.
 - The number of carrier proteins in cell membranes.

## Co-Transport

Co-transport is the mechanism of transport of glucose and amino acid into the epithelial cells in the ileum. Sodium binds to co-transporter proteins to allow glucose and amino acid to be transported.

### Sodium-potassium ATPase

![Sodium-potassium ATPase](https://image-v2.cdn.app.senecalearning.com/2018-09/f98b01b5-ff83-4052-befc-2f2a3ceea884/sodium-potassium%20pump.jpg)

- Sodium ions are actively transported into the blood by sodium-potassium ATPase, from the inside of epithelial cells lining the ileum.
- The concentration of Na+ is now lower inside the cell than outside.

### Sodium-glucose cotransporter

![Sodium-glucose cotransporter](https://image-v2.cdn.app.senecalearning.com/2018-09/21164230-a241-491d-8b83-d1d180ccb563/Cotransport-transport-cell-membrane-exchange-.png)

- Two Na+ ions from the lumen of the ileum bind to a transmembrane protein known as the sodium-glucose cotransporter.
- At the same time, the cotransporter binds with a molecule of glucose from the ileum and moves it into the cell.
- The sodium ions diffuse into the cell, moving the glucose into the cell at the same time.

## Transport in Cells

The three main forms of transport in cells are:

### Diffusion

![Diffusion](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.1%20Diffusion%20of%20gases-min.png)

- Diffusion is the net movement of particles from an area of high concentration to an area of lower concentration.
- Diffusion is an example of passive transport.

### Osmosis

![Osmosis](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.2%20Osmosis/1.3.3%20Osmosis%20(s)-min.jpg)

- Osmosis is a special case of diffusion where only water molecules move.
- Osmosis requires a partially permeable membrane.
- Osmosis is an example of passive transport.

### Active transport

![Active transport](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.4%20Active%20transport%20(2)-min.png)

- Active transport is the net movement of particles against a concentration gradient. 
- So, energy is required.

## Test yourself on Active Transport

- Which of the following processes does NOT happen via active transport?
- Which of the following statements about cotransport are true?
- Which ion binds to cotransporter proteins to transport glucose into the epithelial cells in the ileum?
- Which enzyme actively transports sodium ions into the bloodstream?
- Which of diffusion, osmosis and active transport are examples of passive transport?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/83e90d6d-8d3e-4e59-a2df-b5a5e1957f6c/section/2ff1cef7-8324-42ca-8172-6a19b310c947/session)

- Previous topic: [4.8.3 Osmosis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-3-osmosis.md)
- Next topic: [4.9.1 Power & Efficiency](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-1-power-and-efficiency.md)

## Applied Science: BTEC Level 3 National Extended Diploma contents

### 1 Principles of Science I
- 1.1 Structure & Bonding
  - [1.1.1 Atomic Model](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-1-atomic-model.md)
  - [1.1.2 Electron Shells, Sub-Shells & Orbitals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-2-electron-shells-sub-shells-and-orbitals.md)
  - [1.1.3 Ionic Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-3-ionic-bonding.md)
  - [1.1.4 Representing Ionic Bonds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-4-representing-ionic-bonds.md)
  - [1.1.5 Covalent Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-5-covalent-bonding.md)
  - [1.1.6 Representing Covalent Bonds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-6-representing-covalent-bonds.md)
  - [1.1.7 Metallic Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-7-metallic-bonding.md)
  - [1.1.8 Intermolecular Forces](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-8-intermolecular-forces.md)
  - [1.1.9 Intermolecular Forces 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-9-intermolecular-forces-2.md)
  - [1.1.10 End of Topic Test - Bonding](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-10-end-of-topic-test-bonding.md)
  - [1.1.11 Relative Masses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-11-relative-masses.md)
  - [1.1.12 The Mole](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-12-the-mole.md)
  - [1.1.13 Molar Calculations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-13-molar-calculations.md)
  - [1.1.14 Molar Calculations 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-14-molar-calculations-2.md)
  - [1.1.15 Empirical & Molecular Formulae](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-15-empirical-and-molecular-formulae.md)
  - [1.1.16 Balanced Equations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-16-balanced-equations.md)
  - [1.1.17 Percentage Yield](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-17-percentage-yield.md)
  - [1.1.18 End of Topic Test - Amount of Substance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-1-18-end-of-topic-test-amount-of-substance.md)
- 1.2 Properties of Substances
  - [1.2.1 The Periodic Table](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-1-the-periodic-table.md)
  - [1.2.2 Ionisation Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-2-ionisation-energy.md)
  - [1.2.3 Factors Affecting Ionisation Energies](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-3-factors-affecting-ionisation-energies.md)
  - [1.2.4 Trends of Ionisation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-4-trends-of-ionisation.md)
  - [1.2.5 Trends in the Periodic Table](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-5-trends-in-the-periodic-table.md)
  - [1.2.6 Polarity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-6-polarity.md)
  - [1.2.7 Metals & Non-Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-7-metals-and-non-metals.md)
  - [1.2.8 Alkali Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-8-alkali-metals.md)
  - [1.2.9 Alkaline Earth Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-9-alkaline-earth-metals.md)
  - [1.2.10 Reactivity of Alkaline Earth Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-10-reactivity-of-alkaline-earth-metals.md)
  - [1.2.11 Redox](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-11-redox.md)
  - [1.2.12 Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-12-transition-metals.md)
  - [1.2.13 Redox Reactions of Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-2-13-redox-reactions-of-transition-metals.md)
- 1.3 Cell Structure & Function
  - [1.3.1 Introduction to Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-1-introduction-to-cells.md)
  - [1.3.2 Prokaryotes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-2-prokaryotes.md)
  - [1.3.3 Organelles of Eukaryotic Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-3-organelles-of-eukaryotic-cells.md)
  - [1.3.4 Organelles of Eukaryotic Cells 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-4-organelles-of-eukaryotic-cells-2.md)
  - [1.3.5 Organelles in Plant Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-5-organelles-in-plant-cells.md)
  - [1.3.6 Microscopy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-6-microscopy.md)
  - [1.3.7 End of Topic Test - Cell Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-3-7-end-of-topic-test-cell-structure.md)
- 1.4 Cell Specialisation
  - [1.4.1 Cell Specialisation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-1-cell-specialisation.md)
  - [1.4.2 Blood Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-2-blood-cells.md)
  - [1.4.3 Plant Cells](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-3-plant-cells.md)
  - [1.4.4 Gametes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-4-4-gametes.md)
- 1.5 Tissue Structure & Function
  - [1.5.1 Human Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-1-human-gas-exchange.md)
  - [1.5.2 Blood Vessels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-2-blood-vessels.md)
  - [1.5.3 Atherosclerosis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-3-atherosclerosis.md)
  - [1.5.4 Skeletal Muscle](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-4-skeletal-muscle.md)
  - [1.5.5 Slow & Fast Twitch Fibres](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-5-slow-and-fast-twitch-fibres.md)
  - [1.5.6 Neurones](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-6-neurones.md)
  - [1.5.7 Speed of Transmission](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-7-speed-of-transmission.md)
  - [1.5.8 Action Potentials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-8-action-potentials.md)
  - [1.5.9 End of Topic Test - Neurones & Action Potentials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-9-end-of-topic-test-neurones-and-action-potentials.md)
  - [1.5.10 Synapses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-10-synapses.md)
  - [1.5.11 Types of Synapse](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-11-types-of-synapse.md)
  - [1.5.12 Medical Application](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-12-medical-application.md)
  - [1.5.13 End of Topic Test - Synapses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-13-end-of-topic-test-synapses.md)
  - [1.5.14 Chemical Brain Imbalances](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-14-chemical-brain-imbalances.md)
  - [1.5.15 Effect of Drugs on the Brain](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-5-15-effect-of-drugs-on-the-brain.md)
- 1.6 Working with Waves
  - [1.6.1 Progressive Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-1-progressive-waves.md)
  - [1.6.2 Wave Speed & Phase Difference](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-2-wave-speed-and-phase-difference.md)
  - [1.6.3 Longitudinal & Transverse Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-3-longitudinal-and-transverse-waves.md)
  - [1.6.4 Stationary Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-4-stationary-waves.md)
  - [1.6.5 Stationary Waves 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-5-stationary-waves-2.md)
  - [1.6.6 Applications of Stationary Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-6-applications-of-stationary-waves.md)
  - [1.6.7 Interference](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-7-interference.md)
  - [1.6.8 Diffraction](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-8-diffraction.md)
  - [1.6.9 Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-9-diffraction-gratings.md)
  - [1.6.10 Application of Diffraction Gratings](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-6-10-application-of-diffraction-gratings.md)
- 1.7 Waves in Communication
  - [1.7.1 Refraction at a Plane Surface](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-1-refraction-at-a-plane-surface.md)
  - [1.7.2 Internal Reflection & Fibre Optics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-2-internal-reflection-and-fibre-optics.md)
  - [1.7.3 Applications of Total Internal Reflection](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-3-applications-of-total-internal-reflection.md)
  - [1.7.4 Properties](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-4-properties.md)
  - [1.7.5 Gamma, X-Ray & UV Light](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-5-gamma-x-ray-and-uv-light.md)
  - [1.7.6 Visible Light](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-6-visible-light.md)
  - [1.7.7 Infrared, Microwave & Radio Waves](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-7-infrared-microwave-and-radio-waves.md)
  - [1.7.8 Intensity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-8-intensity.md)
  - [1.7.9 Digital & Analogue Signals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-9-digital-and-analogue-signals.md)
  - [1.7.10 Communication Channels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/1-7-10-communication-channels.md)

### 2 Practical Scientific Procedures and Techniques
- 2.1 Titration
  - [2.1.1 pH Curves & Titrations](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-1-ph-curves-and-titrations.md)
  - [2.1.2 pH Curves & Titrations 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-2-ph-curves-and-titrations-2.md)
  - [2.1.3 Buffer Solutions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-1-3-buffer-solutions.md)
- 2.2 Colorimetry
  - [2.2.1 Measuring Rates](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-2-1-measuring-rates.md)
  - [2.2.2 Beer-Lambert Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-2-2-beer-lambert-law.md)
- 2.3 Chromatography
  - [2.3.1 Overview of Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-1-overview-of-chromatography.md)
  - [2.3.2 Thin-Layer Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-2-thin-layer-chromatography.md)
  - [2.3.3 Column Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-3-column-chromatography.md)
  - [2.3.4 Gas Chromatography](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/2-3-4-gas-chromatography.md)

### 3 Science Investigation Skills
- 3.1 Scientific Processes
  - [3.1.1 Aims, Hypotheses & Sampling](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-1-aims-hypotheses-and-sampling.md)
  - [3.1.2 Pilot Studies & Design](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-2-pilot-studies-and-design.md)
  - [3.1.3 Ethics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-3-ethics.md)
  - [3.1.4 Variables & Control](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-4-variables-and-control.md)
  - [3.1.5 Demand Characteristics & Investigator Effects](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-5-demand-characteristics-and-investigator-effects.md)
  - [3.1.6 Features of Science](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-6-features-of-science.md)
  - [3.1.7 Scientific Report](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-7-scientific-report.md)
  - [3.1.8 Scientific Report 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-1-8-scientific-report-2.md)
- 3.2 Data Handling & Analysis
  - [3.2.1 Types of Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-1-types-of-data.md)
  - [3.2.2 Descriptive Statistics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-2-descriptive-statistics.md)
  - [3.2.3 Presentation & Display of Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-2-3-presentation-and-display-of-data.md)
- 3.3 Enzymes in Action
  - [3.3.1 Overview of Protein Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-1-overview-of-protein-structure.md)
  - [3.3.2 Enzymes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-2-enzymes.md)
  - [3.3.3 Factors Affecting Enzyme Activity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-3-factors-affecting-enzyme-activity.md)
  - [3.3.4 Enzyme-Controlled Reactions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-3-4-enzyme-controlled-reactions.md)
- 3.4 Diffusion
  - [3.4.1 Diffusion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-4-1-diffusion.md)
- 3.5 Plants & Their Environment
  - [3.5.1 Factors Affecting Plant Growth](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-5-1-factors-affecting-plant-growth.md)
  - [3.5.2 Measuring Number & Distribution of Species](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-5-2-measuring-number-and-distribution-of-species.md)
- 3.6 Energy Content in Fuels
  - [3.6.1 Fractions](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-1-fractions.md)
  - [3.6.2 Burning Hydrocarbons](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-2-burning-hydrocarbons.md)
  - [3.6.3 Combustion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-3-combustion.md)
  - [3.6.4 Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-4-energy.md)
  - [3.6.5 Energy at Home](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-5-energy-at-home.md)
  - [3.6.6 Calorimetry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-6-6-calorimetry.md)
- 3.7 Electrical Circuits
  - [3.7.1 Circuit Diagrams & Components](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-1-circuit-diagrams-and-components.md)
  - [3.7.2 Diodes, LDRs & Thermistors](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-2-diodes-ldrs-and-thermistors.md)
  - [3.7.3 Resistance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-3-resistance.md)
  - [3.7.4 Electrical Work](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-4-electrical-work.md)
  - [3.7.5 Ohm's Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-5-ohms-law.md)
  - [3.7.6 Domestic Uses of Electricity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-6-domestic-uses-of-electricity.md)
  - [3.7.7 Fuses](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/3-7-7-fuses.md)

### 4 Principles of Science II
- 4.1 Extracting Elements
  - [4.1.1 Atom Economy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-1-1-atom-economy.md)
- 4.2 Relating Properties to use of Substances
  - [4.2.1 Group 2 Chemistry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-1-group-2-chemistry.md)
  - [4.2.2 End of Topic Test - Group 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-2-end-of-topic-test-group-2.md)
  - [4.2.3 Electrolysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-3-electrolysis.md)
  - [4.2.4 Electrolysis Examples](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-4-electrolysis-examples.md)
  - [4.2.5 Extracting Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-5-extracting-metals.md)
  - [4.2.6 Transition Metals](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-6-transition-metals.md)
  - [4.2.7 Variable Oxidation States](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-7-variable-oxidation-states.md)
  - [4.2.8 Heterogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-8-heterogeneous-catalysts.md)
  - [4.2.9 Homogeneous Catalysts](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-2-9-homogeneous-catalysts.md)
- 4.3 Organic Chemistry
  - [4.3.1 Naming Compounds](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-1-naming-compounds.md)
  - [4.3.2 Functional Groups](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-2-functional-groups.md)
  - [4.3.3 Isomerism](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-3-isomerism.md)
  - [4.3.4 Hydrocarbons](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-4-hydrocarbons.md)
  - [4.3.5 Structure of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-5-structure-of-alkanes.md)
  - [4.3.6 Boiling Points of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-6-boiling-points-of-alkanes.md)
  - [4.3.7 Alkenes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-7-alkenes.md)
  - [4.3.8 Curly Arrows & Mechanisms](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-8-curly-arrows-and-mechanisms.md)
  - [4.3.9 Cracking](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-9-cracking.md)
  - [4.3.10 Combustion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-10-combustion.md)
  - [4.3.11 Free Radical Substitution of Alkanes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-11-free-radical-substitution-of-alkanes.md)
  - [4.3.12 Electrophilic Addition of Alkenes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-3-12-electrophilic-addition-of-alkenes.md)
- 4.4 Energy Changes in Industry
  - [4.4.1 The Kelvin Scale](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-1-the-kelvin-scale.md)
  - [4.4.2 Enthalpy Changes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-2-enthalpy-changes.md)
  - [4.4.3 Calorimetry](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-3-calorimetry.md)
  - [4.4.4 Bond Enthalpies](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-4-bond-enthalpies.md)
  - [4.4.5 Hess' Law](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-4-5-hess-law.md)
- 4.5 The Circulatory System
  - [4.5.1 The Circulatory System](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-1-the-circulatory-system.md)
  - [4.5.2 Blood Vessels](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-2-blood-vessels.md)
  - [4.5.3 Blood Transfusion & the ABO Rhesus System](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-3-blood-transfusion-and-the-abo-rhesus-system.md)
  - [4.5.4 The Heart](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-4-the-heart.md)
  - [4.5.5 The Cardiac Cycle](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-5-the-cardiac-cycle.md)
  - [4.5.6 Cardiac Output](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-6-cardiac-output.md)
  - [4.5.7 Coordination of Heart Action](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-7-coordination-of-heart-action.md)
  - [4.5.8 Heart Dissection](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-8-heart-dissection.md)
  - [4.5.9 Controlling Heart Rate](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-9-controlling-heart-rate.md)
  - [4.5.10 Electrocardiograms](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-10-electrocardiograms.md)
  - [4.5.11 Cardiovascular Disease](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-11-cardiovascular-disease.md)
  - [4.5.12 Investigating Heart Rates](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-5-12-investigating-heart-rates.md)
- 4.6 Ventilation & Gas Exchange
  - [4.6.1 Human Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-1-human-gas-exchange.md)
  - [4.6.2 Ventilation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-2-ventilation.md)
  - [4.6.3 Measuring Gas Exchange](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-3-measuring-gas-exchange.md)
  - [4.6.4 Controlling Ventilation Rate](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-4-controlling-ventilation-rate.md)
  - [4.6.5 Lung Disease](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-5-lung-disease.md)
  - [4.6.6 Lung Disease Data](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-6-6-lung-disease-data.md)
- 4.7 Urinary System
  - [4.7.1 Kidneys & Control of Water Balance](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-1-kidneys-and-control-of-water-balance.md)
  - [4.7.2 Kidneys & Osmoregulation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-2-kidneys-and-osmoregulation.md)
  - [4.7.3 Kidneys & Blood Pressure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-3-kidneys-and-blood-pressure.md)
  - [4.7.4 Urine](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-4-urine.md)
  - [4.7.5 Kidney Failure & Urinalysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-5-kidney-failure-and-urinalysis.md)
  - [4.7.6 Dialysis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-6-dialysis.md)
  - [4.7.7 Transplants](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-7-transplants.md)
- 4.8 Cell Transport
  - [4.8.1 Cell Membrane Structure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-1-cell-membrane-structure.md)
  - [4.8.2 Diffusion](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-2-diffusion.md)
  - [4.8.3 Osmosis](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-3-osmosis.md)
  - [4.8.4 Active Transport](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-8-4-active-transport.md)
- 4.9 Thermal Physics
  - [4.9.1 Power & Efficiency](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-1-power-and-efficiency.md)
  - [4.9.2 Work & Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-2-work-and-energy.md)
  - [4.9.3 Conservation of Energy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-3-conservation-of-energy.md)
  - [4.9.4 Pressure](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-4-pressure.md)
  - [4.9.5 First Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-5-first-law-of-thermodynamics.md)
  - [4.9.6 Second Law of Thermodynamics](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-6-second-law-of-thermodynamics.md)
  - [4.9.7 Heat Engines, Heat Pumps & Refrigerators](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-7-heat-engines-heat-pumps-and-refrigerators.md)
  - [4.9.8 Non-Flow Processes](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-8-non-flow-processes.md)
  - [4.9.9 p-V Diagrams](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-9-p-v-diagrams.md)
  - [4.9.10 Ideal Gases](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-10-ideal-gases.md)
  - [4.9.11 Ideal Gases 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-11-ideal-gases-2.md)
  - [4.9.12 Thermal Energy Transfer](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-12-thermal-energy-transfer.md)
  - [4.9.13 Thermal Energy Transfer Experiments](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-9-13-thermal-energy-transfer-experiments.md)
- 4.10 Materials
  - [4.10.1 Density](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-1-density.md)
  - [4.10.2 Stress & Strain](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-2-stress-and-strain.md)
  - [4.10.3 Properties of Materials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-3-properties-of-materials.md)
  - [4.10.4 Elasticity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-4-elasticity.md)
  - [4.10.5 Plasticity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-5-plasticity.md)
  - [4.10.6 Energy in Materials](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-6-energy-in-materials.md)
  - [4.10.7 Young Modulus](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-10-7-young-modulus.md)
- 4.11 Fluids
  - [4.11.1 Fluid Flow](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-1-fluid-flow.md)
  - [4.11.2 Viscosity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-2-viscosity.md)
  - [4.11.3 Density](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-3-density.md)
  - [4.11.4 Continuity Equation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-4-continuity-equation.md)
  - [4.11.5 Bernoulli's Equation](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-5-bernoullis-equation.md)
  - [4.11.6 Non-Newtonian Fluids](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-11-6-non-newtonian-fluids.md)

### 5 Contemporary Issues in Science
- 5.1 Contemporary Issues in Science
  - [5.1.1 Sustainability](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-1-sustainability.md)
  - [5.1.2 Genetic Engineering](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-2-genetic-engineering.md)
  - [5.1.3 Uses of Genetic Modification](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-3-uses-of-genetic-modification.md)
  - [5.1.4 Stem Cell Therapy](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-4-stem-cell-therapy.md)
  - [5.1.5 Cloning](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-5-cloning.md)
  - [5.1.6 Cloning 2](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-6-cloning-2.md)
  - [5.1.7 Nanotechnology](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-7-nanotechnology.md)
  - [5.1.8 Ecosystems](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-1-8-ecosystems.md)
- 5.2 Analysing Scientific Information
  - [5.2.1 Validity](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-2-1-validity.md)
  - [5.2.2 Peer Review](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/5-2-2-peer-review.md)
