Enzyme Action 4.1

Question 1

What are enzymes?

Answer 1

They are biological catalysts that speed up reactions without being used up themselves.

Question 2

What type of protein is an enzyme?

Answer 2

Globular protein

Question 3

What type of reactions do enzymes catalyse?

Answer 3

Anabolic and Catabolic

Question 4

Anabolic Reaction

Answer 4

Building up molecules e.g starch built up from glucose

Question 5

Catabolic Reaction

Answer 5

Breaking down large molecules e.e break down of starch to release glucose needed for respiration

Question 6

Metabolism

Answer 6

Sum of all the reactions that take place in an organism and can only happen as a result of enzymes

Question 7

Vmax

Answer 7

The maximum rate that the enzymes can speed up a reaction to.

Question 8

How do you increase the rate of a reaction normally?

Answer 8

By increasing the temperature, you’re increasing the kinetic energy in the particles so they move quicker and collide more often. Increasing the pressure means there are more particles in one space so a greater chance of successful collisions.

Question 9

Activation energy

Answer 9

This is the minimum amount of energy required for a reaction to start. Sometimes it’s not enough by itself so it can be sped up by an enzyme which helps molecules collide successfully to reduce the activation energy.

Question 10

Active site

Answer 10

This is an area within the tertiary structure of an enzyme that is folded in a shape that is specific to only one type of substrate.

Question 11

How do ES complexes form?

Answer 11

A substrate will bind to the active site of the enzyme and the R-groups on the enzyme will interact and form temporary bonds to put pressure on the substrate bonds. This forms an ES complex and the substrate can form its product.

Question 12

Induced Fit Hypothesis

Answer 12

This is the theory that as substrates bind to the enzyme the interaction is weak but induces a change in the tertiary structure of the enzyme to make it fit better. This then puts pressure on substrate bonds and lowers activation energy.

Question 13

Intracellular Enzymes

Answer 13

Catalase works inside the cells and breaks down hydrogen peroxide which is a toxic byproduct of metabolism

Question 14

Extracellular Enzymes

Answer 14

Works outside the cell and is used for digestion as many reactions need substrates to synthesis things so polymers need to be broken down outside the cell as they are too big to fit through.

Question 15

How is starch digested?

Answer 15

Starch is broken down into maltose which is a disaccharide by the enzyme amylase. Maltose is broken down into glucose by maltase and then glucose is absorbed in the bloodstream.

Question 16

How is protein digested?

Answer 16

Protein is digested by trypsin which is a protease enzyme. They get broken down into smaller peptides which then get broken down into amino acids by other proteases and absorbed into the blood.