Higher level Enzymes

Question 1

what is an active site?

Answer 1

The Active site is the part of the enzyme that combines with
the substrate.

It is not a rigid shape and changes shape slightly when the
enzyme comes in contact with the substrate.

Question 2

What odes it mean by the substrate inducing the active site?

Answer 2

Often the active site is larger than the substrate so the active site changes shape slightly so that when they come in contact the substrate fits precisely into the active site.

Question 3

Explain the steps of the induced fit model

Answer 3

The substrate combines with the active site of the enzyme.

The active site is induced or caused to change shape slightly
by the substrate.

The substrate and enzyme form an enzyme-substrate
complex. The bonds in the substrate are altered so that the
substrate changes into the products.

The products leave the active site.

The active site returns to
its original shape and is ready for a new substrate.

Question 4

What does enzyme specificity mean?

Answer 4

Enzyme specificity means that each enzyme will react with
only one particular substrate

Question 5

What does optimum ph mean?

Answer 5

Optimum pH refers to the pH at which the enzyme will work
best.

Pepsin 2 and other enzymes 6-8

Question 6

What does optimum temperature mean?

Answer 6

Optimum temperature refers to the temperature at which the
enzyme will work best

20-10 degrees for plant enzymes and 37 for animal enzymes

Question 7

What causes denaturation?

Answer 7

Proteins heated above 40o

Outside optimum ph.

Some chemicals and radiation.

Question 8

What is a denatured enzyme?

Answer 8

A denatured enzyme has lost its shape and can no longer
carry out its function.

Question 9

What is the affect of denaturation on an enzyme?

Answer 9

It causes the enzymes to lost their 3d shape so the active site loses its shape and therefore its ability to bind with the correct substrate so loses its biological activity.

Question 10

Why can ATP not store energy for long?

Answer 10

ATP cannot store energy for very long it breaks down
releasing energy and converting back to ADP

Question 11

What does ADP stand for?

Answer 11

ADP is an abbreviation for Adenosine Diphosphate and is a low energy molecule found in all organisms cells

Question 12

What happens if another phosphate is added to ADP?

Answer 12

It forms ATP (Adenosine Triphosphate)
Extra energy is also added as there is an extra bond between
the last two phosphate groups.

Question 13

what IS THE PROCESS CALLED WHERE BY A PHOSPHATE GROUP IS ADDED TO A MOLECULE?

Answer 13

Addition of a phosphate like this is called Phosphorylation.

Question 14

What happen with ATP when it breaks down and explain its use

Answer 14

When ATP breaks down it releases energy and a phosphate to form ATP. The energy is released from the last bond between the two phosphate groups.

It is used to carry out reactions in cells as it provides energy for cells so they can perform cell functions. Eg brain activity and protein production

Question 15

What happens when an extra phosphate is added to ADP?

Answer 15

It forms atp

Extra energy is added in the form of an unstable bond between the last two phosphate group

Atp is an energy rich compound

Question 16

What is NADP+?

Answer 16

NADP+ is a low energy molecule involved in photosynthesis

NADP+ can combine with 2 high energy electrons and a
proton to form NADPH

NADP is said to be reduced to NADPH

Question 17

What is NADPH?

Answer 17

NADPH is a very high energy molecule that is an electron and hydrogen carrier

The energy and hydrogen it contains is used in photosynthesis to form glucose

Question 18

What is NAD+?

Answer 18

Used in respiration
* NAD+ is a low energy molecule.
* When combined with 2 electrons
and one proton, it becomes NADH

Question 19

What is NADH?

Answer 19

NADH is a high energy molecule
- NADH is unstable and so breaks
down to NAD+ and 2 electrons and
1 proton and some energy.*

THis process is oxiation

Question 20

HOW CAN YO REMEBER WHOCH PROCESS USES WHICH ENERGY CARRIER?

Answer 20

Remember P for photosynthesis, NADP+ & NADPH is used
in photosynthesis NAD+ & NADH in respiration

Question 21

What types of metabolism are photosynthesis and respiration

Answer 21

Respiration- catabolic
Photosynthesis- Anabolic

Question 22

What is the name of the enzyme used to test enzyme activity and is also used in immobilised enzyme investigation?

Answer 22

Catalase from yeast

Question 23

What is the product formed in the enzyme related investigations with catalase?

Answer 23

Oxygen AND water

Question 24

What is the substrate in enzyme related investigations/

Answer 24

Hydrogen peroxide

Question 25

What solution hardens alginate beads?

Answer 25

Calcium chloride

Question 26

What chemicals do you need to immobilise catalase?

Answer 26

yeast for catalase Sodium alginate to immobilise the catalase Calcium Chloride Ph buffer solution 9

Question 27

How do you test if the enzyme has been immobilised?

Answer 27

after you have your calcium alginate which have catalase immobilised in them Put them in a separating funnel then in another funnel pour in catalase solution Then dissolve sucrose in some warm water Pour in both funnels and then use a glucose test strip to test the solutions below both separating funnels Sucrase in the enzyme in the yeast which when in contact with the sucrose solution will form fructose and glucose Then use a timer and time the time is takes for the glucose to be present in both solutions

Question 28

What would the results be of the immobilised enzyme investigation with two separating funnels one with just sucrase/yeast solution passed through and the other with calcium alginate beads containing sucrase?

Answer 28

the one with just yeast solution that has the sucrose solution added should form glucose very quickly and the solution should have a cloudy colour the one with the calcium alginate beads will be clearer but will take longer to convert glucose as it takes longer for the sucrose to penetrate the alginate beads and for the products to be released from the beads. the beads can be resued

Question 29

What temp texture was catalase optimum temperature

Answer 29

25

Question 30

Define bio processing

Answer 30

It is the use of microorganisms to form products