Understanding Enzymes: A Comprehensive Quiz

Who first discovered enzymes and in which year?

• Marie Curie in 1898

• Louis Pasteur in 1857

• Anselme Payen in 1833

• Albert Einstein in 1905

What is primarily responsible for the specificity of an enzyme's action?

• The active site

• The cofactor

• The substrate concentration

• The enzyme concentration

What is the role of cofactors in enzyme activity?

• They inhibit the enzyme

• They permanently bind to enzymes

• They decrease the activation energy

• They assist in the enzyme's activity

Which hypothesis suggests that the enzyme changes shape to bind more tightly to its substrate?

• Catalytic Hypothesis

• Binding Hypothesis

• Lock and Key Hypothesis

• Induced Fit Hypothesis

Which model of enzyme action involves the substrate fitting perfectly into the enzyme's active site?

• Substrate Binding Model

• Induced Fit Hypothesis

• Active Site Model

• Lock and Key Hypothesis

What effect does temperature have on enzymes?

• It denatures enzymes at high temperatures

• It decreases substrate concentration

• It has no effect

• It increases enzyme activity indefinitely

How does pH affect enzyme activity?

• No effect on enzyme activity

• Always increases reaction rate

• Increases enzyme stability

• Can denature enzymes at extreme values

What happens when enzyme concentration increases beyond a certain point?

• No further increase in reaction rate

• Reaction rate increases indefinitely

• Reaction rate decreases

• Substrate concentration decreases

What is a non-competitive inhibitor?

• Is always a protein

• Binds to the active site

• Binds away from the active site, changing the enzyme's shape

• Increases the rate of reaction

What describes a competitive inhibitor's action on an enzyme?

• Binds away from the active site, enhancing activity

• Decreases the enzyme's activation energy

• Binds to the active site, blocking substrate binding

• Increases the availability of cofactors