Topic 4

Question 1

What is metabolism

Answer 1

Metabolism is the total of all chemical reactions that occurs in an organism

• Anabolism: reactions that expend energy to build up molecules
• Catabolism: reactions that harvest energy by breaking up molecules

Many of these reactions occur in sequences called biochemical pathway

In such biochemical pathway, the product of one enzyme becomes the substrate for the successive enzyme

Question 2

describe a biochemical pathway

Answer 2

In a biochemical pathway the initial substrate is converted by the first enzyme into a product that becomes an intermediate that is a substrate for the second enzyme. The second enzyme converts this new substrate into a product that is an intermediate substrate for the third enzyme. This repeats as a sequence till the last enzyme and released as the end product.

The enzymes can be soluble or embedded on the membrane