Cell organisation
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Biology practicals
Investigating specimens using microscopes
Investigating the effect of pH on amylase activity
Investigating molecules in food using food tests
Investigating osmosis in potatoes
Investigating the effect of antimicrobials
Investigating limiting factors of photosynthesis
Investigating the rate of respiration
Using field-work techniques
Ecosystems and material cycles
Exchange and transport in animals
Animal coordination, control and homeostasis
Plant structures and their functions
Health, disease and the development of medicines
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Communicable disease
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Aseptic techniques
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Monoclonal antibodies and their uses - Higher
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Calculating BMI and the waist-to-hip ratio
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Natural selection and genetic modification
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Cells and control
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Explainer Video
Summary
Cell organisation
In a nutshell
Many organisms are made up of lots of cells. In order for an organism to function properly, these cells must be organised.
Tissues
Definition
A tissue is a group of similar cells that work together to carry out a specific function.
Example
Epithelial tissue is made up of epithelial cells, which cover specific parts of the body like the inside of the gut.
Organs
Definition
An organ is a group of different tissues that work together to perform a specific function.
Example
The epithelial tissues that line the inside of the gut work with muscle tissues. They make up the stomach, which is an organ.
Organ systems
Definition
An organ system is a group of organs that work together to perform a function.
Example
The digestive system consists of the mouth (1.), salivary glands (2.), oesophagus (3.), stomach (4.), small intestine (5.) and large intestine (6.). These organs work together to break down and absorb food for energy.
FAQs - Frequently Asked Questions
What is an organ system?
An organ system is a group of organs that work together to perform a function.
What is an organ?
An organ is a group of different tissues that work together to perform a specific function.
What is a tissue?
A tissue is a group of similar cells that work together to carry out a specific function.