Unit 3: Cellular Energetics

Question 1

Properties of enzymes

Answer 1

Lower activation energy
Free energy: endergonic or exergonic
Catalysts 
Specificity
Ph sensitive

Question 2

Specificity in enzymes

Answer 2

Acts on a particular substrate, reaction, heat and temp, pH

Question 3

If enzyme is heated too much it will…

Answer 3

Denature

Question 4

How do enzymes effect the rate of biological reactions

Answer 4

Lower the activation energy for reactions, lower the activation energy—faster the reaction

Question 5

Explain how changes to the structure of an enzyme will effect its function..

Answer 5

Proteins change shape and temperature changes.

High temps cause protein to denature and break up.

Question 6

Enzyme and a substrate will form a…

Answer 6

Reaction intermediate

Question 7

Explain how cellular environment affects enzyme activity…

Answer 7

pH, salt concentration, increase in substrate and inhibitor concentrations

Question 8

Why are enzymes so specific

Answer 8

Active site fits only in specific substrate molecules

Question 9

pH environment

Answer 9

Change shape or change properties of substrate to affect binding to active site

Question 10

Increase in salt concentration leads to…

Answer 10

Increasing amount of ions, can denature protein structure. (Tertiary structure)

Question 11

Increase in substrate and inhibitor concentrations leads to..

Answer 11

Increase in the reaction, more colliding with enzyme molecules

Question 12

Metabolism enables organisms to…

Answer 12

Transform the chemical energy stores in molecules into energy used for cellular processes

Question 13

Aerobic respiration vs anaerobic

Answer 13

Aerobic: O2 is present (ATP)
Anaerobic: o2 absent, fermentation

Question 14

What begins cycle of cellular respiration

Answer 14

Acetyl cpA

Question 15

Why must to ATP be used during the energy investment phase

Answer 15

Form 2 phosphate into 3C sugar

Because phosphates used come from ATP, two ATP molecules get used up when phosphate groups are split half

Question 16

What stores the majority of energy in Chemical glucose bonds

Answer 16

ATP

Question 17

In the energy pay off stage, what happens

Answer 17

Four ATP and 2 NADH molecules are made

Three carbon sugar is converted into pyruvate

Question 18

What is the conversion of pyruvate to aceytl coA that occurs before Krebs cycle

Answer 18

Pyruvate reacts with CoA.
Makes CO2, lose oxygen and one carbon
One molecule of NAD+ is recycled to form NADH

Question 19

How is citrate in citric acid cycle formed

Answer 19

Acetyl coA plus oxaloacetate

CO2 released as waste product

Question 20

Important regulation of citric acid cycle

Answer 20

Dehydrogenase

Question 21

Citric acid cycle produces

Answer 21

High energy for ETC to make ATP, carrying electrons

Question 22

ETC converts electrons from ___ and ___ to pass from one molecule to the other,

Answer 22

NADH AND FADH2

Question 23

1 FADH2 yeilds

Answer 23

2 ATP

Question 24

Each electron acceptor is more … than the last

Answer 24

Electronegative

Question 25

Final e- accept r

Answer 25

Oxygen

Question 26

Fermentation makes it possible for…

Answer 26

ATP to be produced w absense of O2.

Question 27

Fermintation begins with

Answer 27

Glycolysis

Question 28

In fermentation, NAD+

Answer 28

Acts as the H+ acceptor during glycolysis and forms end product

Question 29

In fermentation, NADH

Answer 29

2 NADH give energy t convert pyruvate into lactic acid.

Question 30

How much ATP is made in fermentation

Answer 30

2 through recycling NADH and NAD+