Enzymes and Metabolism

Question 1

A fundamental law is that energy can be transformed from one form to another but cannot be created or destroyed

Question 2

Energy can be divided into

Answer 2

• Potential energy: is stored energy

* Kinetic energy: is the energy of movement

Question 3

metabolism

Answer 3

sum total of chemical reaction in an organism

Question 4

1) Anabolic reactions: =

Answer 4

• synthesis (building) of complex molecules from simple molecules; *energy input is required.
• Endergonic

Question 5

Endergonic

Answer 5

reactions consume free energy (+ΔG): Anabolism (creation)

Question 6

Catabolic reactions:

Answer 6

• breaking down of complex molecules into to simpler ones;
• energy is released.
• Exergonic

Question 7

exergonic

Answer 7

Exergonic reactions release free energy (–ΔG): Catabolism (breakdown)

Question 8

Energy currency of cell

Answer 8

ATP

Question 9

chemical equilibrium, ΔG = 0

Answer 9

Amount are equal so they equal zero

Question 10

Catalysts

Answer 10

• speed up the reactions
• is not altered by the reactions.
• Most biological catalysts are enzymes (proteins

Question 11

Many enzymes change shape when they bind to the substrate—

Answer 11

induced fit

Question 12

Some reactions require energy to start the reaction -

Answer 12

activation energy (Ea).

Question 13

Binding of a substrate to the active site of an enzyme produces an-

Answer 13

enzyme substrate complex (ES)

Question 14

Lower curve is with the enzyme, lowering the actions energy

Higher curve without the enzyme, no energy

Question 15

reaction rate:
no enzyme
enzyme

Answer 15

(no enzyme) as the concentration of the substrate increase, the reaction rate increases

(enzyme) as the concentration of the substrate increase, the reaction rate be at maximum rate (speed reaction)

Question 16

inhabiter

Answer 16

molecules that mind to the enzyme to slow down reaction rates

Question 17

2 types of inhabitors:

1. Irreversible inhibition
2. Reversible inhibition (competitive/ non-non-competative)

Answer 17

*Irreversible inhibition: Inhibitor covalently binds to side chains in the active site—permanently inactivates the enzyme

*Reversible inhibition:
-a) Competitive inhibitors compete with the natural substrate for binding sites.
When concentration of competitive inhibitor is reduced, it detaches from the active site.
-b) Noncompetitive inhibitors: Bind to the enzyme at a different site (not the active site).

Question 18

denaturation

Answer 18

enzymes loss its structure and activity at higher temperature.