Enzymes in Breakdown and Synthesis

Enzymes break down…

big molecules

Big molecules

Proteins, lipids (fats and oils) and some carbohydrates

It’s important that organisms are able to break them down into their smaller components so…

they can be used for growth and other life processes

Why it’s important for organisms to break big molecules into smaller components

Many of the molecules in food are too big to pass through the walls of our digestive system so digestive systems break them down into smaller soluble molecules - these can easily pass through the walls of the digestive system allowing them to be absorbed into the bloodstream. They can then pass into cells to be used by the body

What enzyme converts carbohydrates into simple sugars?

Carbohydrase’s (e.g. amylase breaks down starch)

What enzyme converts proteins into amino acids?

Proteases

What enzyme converts lipids into glycerol and fatty acids?

Lipases

What happens when lipids are broken down?

The fatty acids will lower the pH of the solution they are in

Some enzymes…

join molecules together

Organisms need to be able to…

synthesise (to make or produce something, usually a complex molecule, from simpler substances) carbohydrates, proteins and lipids from their smaller components - enzymes are used in the process

Carbohydrates can be synthesised by…

joining together simple sugars

Glycogen synthase is an enzyme that joins together lots of chains of glucose molecules to…

make glycogen (a molecule used to store energy in animals)

Proteins are made by…

joining together amino acids - enzymes catalyse the reactions needed to do this

Lots of enzymes are also involved in the synthesis of lipids…

from fatty acids and glycerol