Chapter 4 - Enzymes

Question 1

what are enzymes

Answer 1

biological catalysts

Question 2

what type of proteins are enzymes

Answer 2

globular

Question 3

what is the name for the reactants

Answer 3

substrates

Question 4

what factors affect the rate of reaction

Answer 4

temperature, pressure, pH

Question 5

what is Vmax

Answer 5

the maximum point enzymes can increase the rate of reaction to

Question 6

what is activation energy

Answer 6

the energy required to start a reaction

Question 7

how do enzymes affect activation energy

Answer 7

they reduce it by making sure the substrates collide successfully

Question 8

what are the two hypotheses for how enzymes interact with substrate molecules

Answer 8

the lock and key hypothesis and the induced fit hypothesis

Question 9

what is the active site

Answer 9

the area where the substrate binds to the enzyme

Question 10

what is the complex called once the substrate has bound to the enzyme

Answer 10

enzyme-substrate complex

Question 11

what is the name given when the product is formed but it is still bound to the enzyme

Answer 11

enzyme-product complex

Question 12

what is different about the induced fit hypothesis

Answer 12

the enzyme’s active site is thought to change shape slightly once the substrate has bound

Question 13

what are intracellular and extracellular enzymes

Answer 13

enzymes which work within cells (intra) or enzymes that work outside of cells (extra)

Question 14

give a use of enzymes in the gut

Answer 14

digestion - breaking down polymers

Question 15

where is starch digested

Answer 15

mouth and small intestine

Question 16

explain how starch is digested

Answer 16

in the mouth amylase breaks starch down into maltose
amylase is produced by the salivary glands and the pancreas
in the small intestine maltose is broken down into glucose by the enzyme maltase

Question 17

where and how are proteins digested

Answer 17

in the small intestine by proteases like trypsin (broken into amino acids)

Question 18

what is the temperature coefficient, Q10

Answer 18

a measure of how much the rate of reaction increases with a 10 degrees temperature rise

Question 19

what happens when the temperature is raised too high

Answer 19

the enzymes will denature - the vibrations cause the bonds to break

Question 20

what is the optimum temperature

Answer 20

the temperature which gives highest yield/rate of activity (in humans this is around 40)

Question 21

what is it called when a protein moves away from its optimum pH and then back to it

Answer 21

renaturation