Introduction

Enzymes are biological catalysts. You must be able to define the terms ‘enzyme’ and ‘catalyst’ and be able to outline the importance of enzymes to organisms and to the chemistry of life.

An understanding of enzymes being proteins with a specific shape is key to understanding how changes in conditions (temperature and pH) affect their activity. You must be able to recall that enzymes have a particular three-dimensional shape and within the enzyme molecule there is a region with a specifically shaped ‘dent’ in it. This shaped ‘dent’ is complimentary to the substrate molecule enabling the enzyme and the substrate to bind briefly and ensuring that the enzyme can catalyse the chemical reaction that changes the substrate molecule into a product molecule.

Reading

Read and make notes on pages 42-44 and 47-49 of your coursebook.

Tasks

Add the keywords to the glossary file and or the Quizlett App.

Make a copy of Fig. B4.02 and include all labels. Complete the in-text questions and check your answers. Alternatives are given to the practical activities.

Links

EXPLORE - Enzymes (Twig) [Not available with sample course]

WATCH – Enzymes – GCSE Science AQA Biology Required Practical (YouTube)

Download

READ - Enzymes (PowerPoint)

Review

Define the term ‘substrate’.

State what an enzyme is and what its role is.

Summarise how enzymes work in no more than five sentences.