100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Summary notes for CIE IGCSE Biology Topic 4: Biological molecules £2.99
Add to cart
Quickly navigate to
Preview
  2.  
  3. GCSE
  4.  
  5. GCSE
  6.  
  7. Biology

Summary

Summary notes for CIE IGCSE Biology Topic 4: Biological molecules

3 reviews
 0 purchase

Complete revision notes for Topic 4 of the CIE IGCSE Biology course: Biological molecules. Explanations with diagrams for every specification point. These notes are written for candidates taking the Extended paper.

Preview 2 out of 7  pages

Document information

  • April 9, 2021
  • 7
  • 2020/2021
  • Summary

Subjects

Written for

All documents for this subject (910)

3  reviews

review-writer-avatar

By: lianadejagerdj • 3 year ago

review-writer-avatar

By: valenting2002 • 3 year ago

review-writer-avatar

By: nimranadeem • 3 year ago

Seller

avatar-seller
williambennett

Reviews received

Content preview

Biological molecules

4.1 Biological molecules

All the molecules in this topic contain carbon and so are described as organic molecules.

List the chemical elements that make up:

 Carbohydrates

C, O and H

 Fats

C, O and H

 Proteins

C, O, H and N
Some contain small amounts of other elements like sulphur

State that large molecules are made from smaller molecules, limited to:

 Starch and glycogen from glucose
 Cellulose from glucose

Long chains of simple sugars
Glucose is a simple sugar (a monosaccharide)
When 2 glucose molecules join together maltose is formed (a disaccharide)
When lots of glucose molecules join together starch, glycogen or cellulose can form (a
polysaccharide)

Polysaccharides:
 Starch (energy store in plants)
 Glycogen (energy store in animals)
 Cellulose (makes up cell walls)

 Proteins from amino acids

Long chains of amino acids
There are about 20 different amino acids
They all contain the same basic structure, but the ‘R’ group is different for each one
When amino acids are joined together a protein is formed
The amino acids can be arranged in any order, resulting in hundreds of thousands of
different proteins

, Even a small difference in the order of the amino acids results in a different protein being
formed




 Fats and oils from fatty acids and glycerol

Most fats (lipids) in the body are made up of triglycerides
Their basic unit is 1 glycerol molecule chemically bonded to 3 fatty acid chains
The fatty acids vary in size and structure
Lipids are divided into fats (solids at room temperature) and oils (liquids at room
temperature)




Explain that different sequences of amino acids give different shapes to protein molecules

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller williambennett. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for £2.99. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

66184 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy revision notes and other study material for 15 years now

Start selling
£2.99
  • (3)
Add to cart
Added