Summary

Summary AQA A-Level Biology Chapter 1: Biological Molecules Revision Notes

0 purchase

Course
Unit 1 - Biological molecules

Institution
AQA

The first chapter of AS AQA Biology: Biological Molecules is summarised in this pdf. These notes were produced in accordance with the updated AQA A-Level Biology Specification. The chapter notes contain all the information you need to understand about proteins, carbohydrates, enzymes, and lipids, a...

[Show more]

Preview 2 out of 9 pages

View example

Uploaded on July 29, 2022
Number of pages 9
Written in 2021/2022
Type Summary

aqa
a level
biology
sixth form
as level
college
gcse
as

Study Level
A/AS Level
Examinator
AQA
Subject
A Level Biology
Unit
Unit 1 - Biological molecules

$3.94

Also available in package deal from $5.26

Add to cart

Save

100% satisfaction guarantee
Immediately available after payment
Both online and in PDF
No strings attached

Also available in package deal (1)

AQA A-Level Biology Section 1: Biological molecules

$ 7.88 $ 5.26 2 items

1. Summary - Aqa a-level biology chapter 1: biological molecules revision notes
2. Summary - Aqa a-level biology nucleic acids notes
Show more

Chapter 1: Biological Molecules

Monomers and Polymers

Monomers are the smaller units from which larger
molecules are made. Monosaccharides, amino acids and
nucleotides are examples of monomers.

Polymers are molecules made from many monomers
joined together.

A condensation reaction joins two Condensation reaction:
molecules together with the formation
of a chemical bond and involves the
elimination of a molecule of water.

A hydrolysis reaction breaks a Hydrolysis reaction:
chemical bond between two
molecules and involves the use of a
water molecule.

Carbohydrates
Monosaccharides are monomers from which larger
carbohydrates are made. They are sweet-tasting, soluble
substances.

Examples of monosaccharides include glucose, galactose and
fructose.

Glucose is a hexose (6-carbon) sugar. It has two isomers:
alpha and beta glucose. Isomers have the same molecular
formula but are arranged differently. The difference
between the two isomers of glucose is that the OH group is
present below Carbon 1 on alpha-glucose but above
Carbon 1 in beta-glucose.

1

, A pair of monosaccharides can be combined to form a
disaccharide.

• Glucose + Glucose = Maltose
• Glucose + Fructose = Sucrose
• Glucose + Galactose = Lactose

When the monosaccharides join, a molecule of water is Fructose is a natural sugar
removed, and the reaction is therefore called a condensation present in fruits, certain
reaction and the bond formed is called a glycosidic bond. When vegetables and honey.
water is added to a disaccharide, it breaks the glycosidic bond
releasing the constituent monosaccharides (hydrolysis).

Polysaccharides are formed by the condensation of many
glucose units. Examples include: Starch, Glycogen and
Cellulose.

Starch Glycogen
Structure: Polysaccharide of a-glucose. Mixture of Structure: Polysaccharides of a-glucose with
amylose and amylopectin; amylose has C1-C4 C1-C4 and C1-C6 glycosidic bonds so is highly
glycosidic bonds so is unbranched, while branched.
amylopectin has C1-C4 and C1-C6 glycosidic bonds
so is branched. Function: Energy store in animal cells.

Function: Energy store in plant cells. Structure relating to function:

Structure relating to function: • It is insoluble and therefore doesn't
affect water potential, so water is not
• It is insoluble and therefore doesn't affect drawn into the cell by osmosis.
water potential, so water is not drawn into • Being large and insoluble, it does not
the cell by osmosis. diffuse out of cells.
• Being large and insoluble, it does not • It is compact, so a lot of it can be
diffuse out of cells. stored in a small space.
• It is compact, so a lot of it can be stored in • It is more highly branched than
a small space. starch and so has more ends that can
• When hydrolysed, it forms a-glucose, be acted on simultaneously by
which is both easily transported and enzymes. Its therefore more rapidly
readily used in respiration. broken down to form glucose
• The branched form has many ends, each of monomers, which are used in
which can be acted on by enzymes respiration. This is important to
simultaneously meaning that glucose animals, which have a higher
monomers are released very rapidly. metabolic rate and therefore
respiratory rate than plants because
they are more active.

2

The benefits of buying summaries with Stuvia:

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

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

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 sankalpsoundararajan. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $3.94. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

65555 documents were sold in the last 30 days

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

Start selling

Seller

Exam (elaborations) ·