Edexcel IGCSE Biology · Spec 2.7-2.8
Biological Molecules
Carbohydrates, proteins and lipids — the elements they contain and the building blocks they are made from.
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Biological Molecules
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Spec 2.7-2.8
What you need to know
- Name the elements in carbohydrates, proteins and lipids
- Describe the building blocks of each
- Recognise their basic structure
Active recall
Quick check
Answer each question before opening the answer.
Which elements are in carbohydrates, lipids and proteins?
Carbohydrates and lipids: carbon, hydrogen and oxygen. Proteins: carbon, hydrogen, oxygen and nitrogen (and often sulfur).
What are the building blocks of starch, lipids and proteins?
Starch — glucose; lipids — fatty acids and glycerol; proteins — amino acids.
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