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Metabolism

Metabolism

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Investigating specimens using microscopes

Investigating osmosis in potatoes

Investigating the effect of pH on amylase activity

Investigating molecules in food using food tests

Investigating limiting factors of photosynthesis

Investigating human reaction times

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Antibiotic resistance: causes and prevention

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The process of genetic engineering - Higher

Classifying living organisms

Homeostasis and response

Homeostasis and blood glucose

The nervous system and the reflex arc

The human endocrine system

Hormones: adrenaline and thyroxine - Higher

Hormones in human reproduction

Treating infertility - Higher

Bioenergetics

Photosynthesis and limiting factors

How plants use glucose from photosynthesis

Factors limiting the rate of photosynthesis - Higher

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Aerobic and anaerobic respiration

Metabolism

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Enzymes

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Cancer and its risk factors

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Water and mineral transport in plants

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Exchange surfaces in leaves and fish

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Comparing results using percentage change

Explainer Video

Tutor: Holly

Summary

Metabolism

In a nutshell

Metabolism is all of the chemical reactions that happen inside an organism. These reactions are controlled by enzymes. The reactions can build up molecules or break them down.



Building up molecules

Some chemical reactions can build up molecules. 


Example

Glucose is an example of a sugar molecule. Lots of glucose molecules can be joined together to form starch, glycogen and cellulose. Starch is a storage molecule in plant cells, glycogen is the equivalent storage molecule in animal cells and cellulose strengthens the plant cell wall.


Example

Lipids are made from three fatty acids and one molecule of glycerol. Glucose is used to make the glycerol which combines with the three fatty acids.


Example

Glucose can be used to make proteins. Sugar molecules will join nitrate ions to form amino acids. Lots of amino acids join together to form proteins.



Breaking down molecules

Some chemical reactions can break down molecules. 


Example

Respiration is the process of breaking down glucose into carbon dioxide and water. This process transfers energy to other metabolic reactions in the body such as protein synthesis.


Example

Urea is formed through the breakdown of excess proteins. The urea is then excreted in urine.


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Learn with Basics

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Exothermic and endothermic reactions and catalysts

Unit 1

Exothermic and endothermic reactions and catalysts

Enzymes

Unit 2

Enzymes

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Metabolism

Unit 3

Metabolism

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FAQs - Frequently Asked Questions

What is an example of metabolism breaking down molecules?

Respiration is the process of breaking down glucose into carbon dioxide and water. This process transfers energy to other metabolic reactions in the body such as protein synthesis.

What is an example of metabolism building up molecules?

Glucose is an example of a sugar molecule. Lots of glucose molecules can be joined together to form starch, glycogen and cellulose.

What is metabolism?

Metabolism is all of the chemical reactions that happen inside an organism.

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