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Biology

Bioenergetics

Metabolism

Select Lesson

Exam Board

Select an option

Biology practicals

Investigating specimens using microscopes

Investigating the effect of pH on amylase activity

Investigating osmosis in potatoes

Investigating limiting factors of photosynthesis

Investigating the rate of respiration

Using field-work techniques

Ecosystems and material cycles

Ecosystems, competition and environmental changes

Human impacts on biodiversity

Conservation and maintaining biodiversity

The carbon cycle

The water cycle

Obtaining potable water

The nitrogen cycle

Exchange and transport in animals

Specialised exchange surfaces

Human circulatory system

Aerobic and anaerobic respiration

Animal coordination, control and homeostasis

The human endocrine system

Hormones: adrenaline and thyroxine - Higher

Hormones in human reproduction

Treating infertility - Higher

Homeostasis and blood glucose

Plant structures and their functions

Photosynthesis and limiting factors

Factors limiting the rate of photosynthesis - Higher

Water and mineral transport in plants

Health, disease and the development of medicines

The relationship between health and disease

Communicable disease

Sexually transmitted infections

How the body fights disease

Vaccination, immunisation and medicines

Drug development and testing

Non-communicable diseases

Calculating BMI and the waist-to-hip ratio

Cardiovascular disease and treatment

Natural selection and genetic modification

Evolution by natural selection

Fossils as evidence for evolution

Classifying living organisms

Selective breeding

Uses and evaluation of genetic engineering

The process of genetic engineering - Higher

Genetics

Meiosis, sexual and asexual reproduction

DNA: structure, genes and chromosomes

Inheritance and genetic diagrams

Inherited disorders

Types and sources of variation

The human genome project

Cells and control

The cell cycle and stages of mitosis

Cell differentiation, stem cells and ethics

The nervous system and the reflex arc

Key concepts

Eukaryotic and prokaryotic cells

Specialised animal and plant cells

Types of microscopes and calculations

Enzymes

Transport systems in cells

Working scientifically

The scientific method

Science communication and ethics

Evaluating risks and hazards

Collecting data

Processing and presenting data

Units and equations

Structuring a scientific report and drawing conclusions

Uncertainties and evaluations

Practical skills

Measuring techniques

Safety and ethics

Designing experiments

Methods of heating substances

Working with electronics

Random sampling and sampling methods

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.

Learn with Basics

Length:

Unit 1

Exothermic and endothermic reactions and catalysts

Unit 2

Enzymes

Jump Ahead

Optional

Unit 3

Metabolism

Final Test

Create an account to complete the exercises

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.

Home

Biology

Bioenergetics

Metabolism

Videos

Summary

Exercises

Select Lesson

Exam Board

Select an option

Biology practicals

Investigating specimens using microscopes

Investigating the effect of pH on amylase activity

Investigating osmosis in potatoes

Investigating limiting factors of photosynthesis

Investigating the rate of respiration

Using field-work techniques

Ecosystems and material cycles

Ecosystems, competition and environmental changes

Human impacts on biodiversity

Conservation and maintaining biodiversity

The carbon cycle

The water cycle

Obtaining potable water

The nitrogen cycle

Exchange and transport in animals

Specialised exchange surfaces

Human circulatory system

Aerobic and anaerobic respiration

Animal coordination, control and homeostasis

The human endocrine system

Hormones: adrenaline and thyroxine - Higher

Hormones in human reproduction

Treating infertility - Higher

Homeostasis and blood glucose

Plant structures and their functions

Photosynthesis and limiting factors

Factors limiting the rate of photosynthesis - Higher

Water and mineral transport in plants

Health, disease and the development of medicines

The relationship between health and disease

Communicable disease

Sexually transmitted infections

How the body fights disease

Vaccination, immunisation and medicines

Drug development and testing

Non-communicable diseases

Calculating BMI and the waist-to-hip ratio

Cardiovascular disease and treatment

Natural selection and genetic modification

Evolution by natural selection

Fossils as evidence for evolution

Classifying living organisms

Selective breeding

Uses and evaluation of genetic engineering

The process of genetic engineering - Higher

Genetics

Meiosis, sexual and asexual reproduction

DNA: structure, genes and chromosomes

Inheritance and genetic diagrams

Inherited disorders

Types and sources of variation

The human genome project

Cells and control

The cell cycle and stages of mitosis

Cell differentiation, stem cells and ethics

The nervous system and the reflex arc

Key concepts

Eukaryotic and prokaryotic cells

Specialised animal and plant cells

Types of microscopes and calculations

Enzymes

Transport systems in cells

Working scientifically

The scientific method

Science communication and ethics

Evaluating risks and hazards

Collecting data

Processing and presenting data

Units and equations

Structuring a scientific report and drawing conclusions

Uncertainties and evaluations

Practical skills

Measuring techniques

Safety and ethics

Designing experiments

Methods of heating substances

Working with electronics

Random sampling and sampling methods

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

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.

Learn with Basics

Length:

Unit 1

Exothermic and endothermic reactions and catalysts

Unit 2

Enzymes

Jump Ahead

Optional

Unit 3

Metabolism

Final Test

Create an account to complete the exercises

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.