Enzymes

Objectives Define enzymes Describe the effect of changes in temperature an pH on enzyme activity

Catalyst: a substance that speeds up a chemical reaction and is not changed by the reaction Scientists say enzymes speed up, or catalyze, roughly 4,000 reactions in the body.

Enzymes: proteins that function as biological catalysts Changes the substrate Into the product Substrate

For example: enzymes break down sugars for digestion

Enzyme Properties All enzymes are proteins Enzymes work best at a particular temp Enzymes are made inactive by high temps Enzymes work best at a particular pH Enzymes are not ‘used up’ in reactions Enzymes are specific

Effect of Temperature on Enzyme Activity As temperature ____________, enzyme activity can _________. However, very high temperatures denature enzymes, or cause them to stop working.

What is pH? pH is a measure of acidity Water has a neutral pH of 7 A change in pH can disrupt an enzyme’s shape and structure causing it to unravel, or denature.

Effect of pH on Enzyme Activity

Enzymes are named for what they catalyze Protease = breaks down Protein Lipase = breaks down Lipids (fats) Carbohydrase = breaks down carbohydrates Maltase = breaks down Maltose Sucrase = breaks down Sucrose Amylase = breaks down Starch What are the substrates and products?

Not All Enzymes Are Created Equal Stomach enzymes work in a super acidic environment of pH 2. A little way down the digestive tract, intestine enzymes need a pH of 8.