ATP

Question 1

What does ATP stand for?

Answer 1

Adenosine triphosphate

Question 2

What is ATP used for?

Answer 2

Energy utilisation

Question 3

What is ADP + Pi used for?

Answer 3

Respiration

Question 4

Which sugar is in ATP?

Answer 4

Ribose

Question 5

Which bond is found in ATP?

Answer 5

2 Phosphoanhydride bonds

Question 6

What is produced when the 2 Phosphoanhydride bonds are hydrolysed?

Answer 6

First bond = ADP

Second bond = AMP

Question 7

How does ATP provide energy?

Answer 7

A small amount of energy is needed to break the phosphate bonds. In the hydrolysis, energy is released. The output energy is greater than the input.

Question 8

List the processes that generate ATP.

Answer 8

Glycolysis 
Kreb's cycle
Oxidative phosphorylation 
Substrate level phosphorylation 
Electron transport chain 
Beta oxidation

Question 9

Where does glycolysis take place?

Answer 9

Cytosol of cytoplasm

Question 10

Is oxygen required for glycolysis?

Answer 10

No, glycolysis can take place in anaerobic conditions

Question 11

Give the simplified reaction of glycolysis.

Answer 11

Glucose + 2ADP + 2Pi + 2NAD+ > 2 Pyruvate + 2ATP + 2NADH + 2H+ + 2H20

Question 12

What does the kinase enzyme do?

Answer 12

Adds/removes a phosphate group

Question 13

What does the isomerase enzyme do?

Answer 13

Rearranges the structure of a substrate without changing the molecular formula.

Question 14

What does the aldolase enzyme do?

Answer 14

Creates or breaks down carbon-carbon bonds.

Question 15

What does the dehyrogenase enzyme do?

Answer 15

Moves H+ to an electron acceptor

Question 16

What does the enolase enzyme do?

Answer 16

Produces a carbon=carbon double bond by removing an OH group

Question 17

In anaerobic conditions, what is pyruvate converted to?

Answer 17

Lactate

Question 18

Give the simplified reaction of glucose to lactate.

Answer 18

Glucose + 2 ADP + 2 Pi > 2 Lactate + 2 ATP + 2 H2O

Question 19

What is the fate of lactate?

Answer 19

1. Some is released into the blood and taken up by the heart & brain to be converted back to pyruvate for energy
2. Some is taken up by the liver to be uses as a precursor for the formation of glucose

Question 20

Why is glycolysis inhibited by acidosis?

Answer 20

Phosphofructokinase-1 (PFK-1) is PH dependent and is inhibited by acidic conditions.

Question 21

What effect does AMP have on PFK-1?

Answer 21

AMP is an allosteric activator. It modifies the active site of PFK-1 which undergoes a conformational change. This increases PFk-1’s affinity for fructose-6-phosphate.

Question 22

What effect does ATP have on PFK-1?

Answer 22

ATP is an allosteric inhibitor. Modifies active site of PFK-1 so that its affinity for the substrate decreases.

Question 23

Where does the Kreb’s cycle take place?

Answer 23

Mitochondrial matrix.

Question 24

Give the simplified reaction of the Kreb’s cycle.

Answer 24

Acetyl CoA + 3NAD+ + FAD + GDP + ADP + Pi + 2H2O > 2CO2 + CoA + 3 NADH +
3H+ + FADH2 + GTP + ATP

Question 25

How is acetyl CoA made?

Answer 25

From pyruvate or the beta-oxidation of fatty acids

Question 26

Is oxygen required for the Kreb's cycle to take place?

Answer 26

Yes, aerobic conditions are needed.

Question 27

Where does oxidation of fatty acids take place?

Answer 27

Mitochondria

Question 28

Give the equation for fatty acid activation.

Answer 28

Fatty acid + ATP + CoA > Acyl-CoA + PPi (pyrophosphate) + AMP

Question 29

Which molecule must Acyl CoA be converted to in order to pass through the outer mitochondrial membrane?

Answer 29

Acyl carnitine

Question 30

What is the carnitine shuttle?

Answer 30

The process of acyl carnitine being converted back to acycl CoA in the mitochondria. The carnitine then diffuses out of the membrane to convert more acyl CoA to acyl carnitine

Question 31

What are the products of one round of beta-oxidation?

Answer 31

1 mol of NADH, 1 mol of FADH2 + 1 mol of acetyl CoA

Question 32

How much ATP is produced from 1 mol of 18-carbon fatty acid?

Answer 32

146 moles

Question 33

How much ATP is produced from 1 mol of glucose?

Answer 33

38 moles

Question 34

Why aren't fatty acids uses as a fuel source for the nervous system?

Answer 34

They cannot get through the blood-brain barrier.

Question 35

Name a fatty acid.

Answer 35

Oleic acid, palmitic acid

Question 36

Where does oxidative phosphorylation occur?

Answer 36

Inner mitochondrial membrane

Question 37

How does the electron transport chain work?

Answer 37

Two electrons from hydrogen atoms are transferred from NADH+, H+ or FADH2 to one of the proteins in the electron transport chain. They are transferred to oxygen to make water. This process regenerates the hydrogen free forms of NAD & FAD which become available to accept two more hydrogens from intermediates in the Kreb's cycle.

Question 38

What is the energy released from transferring electrons between proteins down the transport chain used for?

Answer 38

Cytochromes pump hydrogen ions from the matrix into the intermembranal space. Creates a hydrogen ion concentration gradient.

Question 39

What do hydrogen ions flow through from the membrane to the matrix of the mitochondria? What is the energy released used for?

Answer 39

ATP synthase channels. They move by chemiosmosis. The energy released is converted to chemical bond energy to catalyse the formation of ATP from ADP + Pi.

Question 40

What is the overall reaction for respiration?

Answer 40

C6H12O6 + 6O2 + 38 ADP + 38 Pi > 6CO2 + 6H20 + 34-38 ATP