Source: https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-6-dialysis

[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) › Dialysis

# Dialysis

Applied Science: BTEC Level 3 National Extended Diploma, topic 4.7.6

## Dialysis

Dialysis is one possible treatment for kidney failure. It is an essential treatment for people whose kidneys cannot keep the concentrations of urea and salt at an optimum level to ensure that tissue damage does not occur.

### The dialysis machine

![The dialysis machine](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/dialysis.jpg)

- The patient is linked up to the dialysis machine and their blood flows into the machine.
- The machine contains a fluid that is designed to have the optimum concentrations of salts (e.g. sodium and potassium ions) and glucose, as would be found in a healthy person’s blood.

### The dialysis fluid

![The dialysis fluid](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/5.3.4a%20-%20Blood%20Waste%20removed%20Urea-min.jpg)

- The patient's blood passes over a partially permeable membrane in the machine that is designed to replicate the kidney tubules. 
- The dialysis fluid is on the other side of the membrane. A concentration gradient is established, allowing excess ions and urea to diffuse from an area of high concentration in the patient’s blood to an area of low concentration in the dialysis fluid.

## The Advantages and Disadvantages of Dialysis

Dialysis has advantages and disadvantages.

### Advantages

![Advantages](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/life-saver-ring-1612456_640-min.jpg)

- Dialysis is a life-saving process.
- It gives a patient more time to find a donor kidney.

### Disadvantages

![Disadvantages](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/rolex-2171960_640-min.jpg)

- Lasts 3-4 hours and is needed 3 times a week.
- Increases risk of blood clots and infections. 
- Expensive process.

## Test yourself on Dialysis

- What diffuses from the patient's blood to the dialysis fluid via a concentration gradient?
- Dialysis is one possible treatment for kidney failure. Which of the following are also true of dialysis?
- How many times a week must dialysis be performed?

[Practise this topic for free](https://app.senecalearning.com/classroom/course/83e90d6d-8d3e-4e59-a2df-b5a5e1957f6c/section/bdbef26a-824c-4d35-a0f6-b5b41623d343/session)

- Previous topic: [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)
- Next topic: [4.7.7 Transplants](https://senecalearning.com/en-gb/revision-notes/btec/science/applied-science-btec-level-3/4-7-7-transplants.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)
