Enzyme Structure and Function

Why do we study molecules in biology?

Review the large molecules of life: break down into

break down into

break down into

Large molecules in food are broken down into smaller molecules to:

– Provide energy to the body– Provide building blocks to make new

molecules

Enzymes

Are specialized proteins that help:– Catalyze (“speed up”) reactions– Break down molecules– Build up new molecules

And can be affected by changes in the enzyme’s environment – their activity or effectiveness

Enzymes are specific in how they work!– Substrate– Active Site

For the audio-visual learners…

• Enzyme video clip from Bozeman Biology

• The enzyme song!

• Enzymes lower the activation energy of a chemical reaction.

• Activation energy is the amount of energy it takes for a reaction to “go”

• Inhibitors can get in the way!

• These are molecules that interfere with enzyme function.– Competitive Inhibitors– Non-competitive

Inhibitors (“allosteric”)

• Can slow the work of enzymes, or stop it altogether.

Enzyme Structure and Function

Write your summary

paragraph

Your Tasks/Homework

• Read text excerpts,– A specific enzyme catalyzes each cellular

reaction– Enzyme inhibitors block enzyme action and

can regulate enzyme activity in a cell

• Answer follow-up questions on sheet

Respond to these questions in the spaces below.

• What does “induced fit” refer to, when talking about enzymes?

• Explain how an enzyme speeds up a specific reaction.• What does it mean to be an optimal condition for an

enzyme”?• List 2 optimal enzyme conditions for humans.• Compare and contrast cofactors and coenzymes. • Compare and contrast competitive inhibitors and non-

competitive inhibitors.• What is the advantage of feedback inhibition to a cell?

Label where enzymes are produced

Quick Review!From essay, What Happens to the Food You Eat?

1. Why is saliva an important component of the digestive system?

2. Explain what happens to food as it passes through the stomach into the small intestine.

3. Why is chewing food such an important function to digestion?

4. How are large molecules broken down into smaller ones?

You Are What You Eat!