Enzyme Quiz no 2,3 biology

Match the following descriptions with the correct definition of a catalyst.

• A substance that speeds up chemical processes without being altered

• A substance that increases the speed of a reaction and is used up

• A substance that slows down chemical processes

• A substance that increases the speed of a reaction and is not changed

• A substance that halts chemical processes

• A substance that decreases the speed of a reaction

• A substance that speeds up chemical processes and is consumed

• A substance that stops a reaction

What type of reactions do enzymes catalyze?

• Physical reactions

• Metabolic reactions

• Nuclear reactions

• Electrical reactions

How do enzymes affect the need for temperature in reactions?

• They increase the need for high temperatures

• They reduce the need for high temperatures

• They have no effect on temperature

• They require extremely high temperatures

What are enzymes made from?

• Carbohydrates

• Lipids

• Proteins

• Nucleic acids

What is the 'lock and key' model?

• A model where the enzyme changes shape to fit the substrate

• A model where the substrate acts as a key fitting the enzyme lock

• A model where the enzyme and substrate are identical

• A model where the substrate changes shape to fit the enzyme

What is produced from an enzyme-substrate reaction?

• A reactant

• A catalyst

• A product

• An inhibitor

Match the following factors with their effects on enzyme function.

• Effect of acidity on enzyme activity

• Only pH

• No effect of heat or acidity on enzyme activity

• Temperature and pH

• Combined effect of heat and acidity on enzyme activity

• Neither temperature nor pH

• Effect of heat on enzyme activity

• Only temperature

What is the optimum temperature for enzyme activity in the human body?

• 25°C

• 37°C

• 50°C

• 100°C

What happens to enzymes above their optimum temperature?

• They become more active

• They become denatured

• They remain unchanged

• They dissolve

The typical optimum pH for enzymes is (a)  

• pH 3
• pH 5
• pH 7
• pH 9