Respiration

Question 1

Name 3 processs animals need energy for

Answer 1

Any 3 from - Muscle contraction, maintenance of body temperature, active transport, DNA replication cell division and protein synthesis

Question 2

What is the overall equation for aerobic respiration?

Answer 2

C6 H12 06 + 602&raquo_space;»» 6C02 + 6H20 + Energy

Question 3

What does anaerobic respiration produce in plants?

Answer 3

Ethanol
C02
Releases energy

Question 4

In humans what does anaerobic respiration produce?

Answer 4

Lactate and releases energy

Question 5

What is the structure of ATP?

Answer 5

Adenine, ribose and three phosphate groups

Question 6

Which enzyme catalyses the synthesis of ATP from ADP + Pi (via a condensation reaction)

Answer 6

ATP Synthase

Question 7

Which enzyme catalyses the hydrolysis reaction from ATP into ADP + Pi?

Answer 7

ATP hydrolase

Question 8

What is the process known as that involves adding phosphate to another molecule

Answer 8

Phosphorylation

Question 9

What properties make ATP a good energy source?

Answer 9

• small soluble molecule so it can be easily transported around the cell
• ATP stores or releases only a small amount of energy at a time so no energy is wasted as heat
• It’s easily broken down, so energy can be released instantaneously
• It can be quickly remade
• It can make other molecules more reactive by transferring one of its phosphate groups to them (phosphorylation)
• ATP can’t pass out the cell so the cell always has an immediate supply of energy

Question 10

What is the compensation point in plants?

Answer 10

The particular level of light intensity at which the rate of photosynthesis exactly matches the rate of respiration

Question 11

Where does gycolysis take place?

Answer 11

Occurs in the cytoplasm of cell

Question 12

What happens in the first stage of glycolysis?

Answer 12

Phosphorylation- 1- glucose is phosphorylated using a phosphate from a molecule of ATP. This creates one molecule of glucose phosphate and 1 molecule of ADP
2- ATP added to another phosphate forming Hexose bisphosphate
3- Hexose bisphosphate is then split into 2 molecules of triose phosphate

Question 13

What happens in the second stage of glycolysis?

Answer 13

Oxidation- Triose phosphate is oxidised (loses hydrogen) forming two molecules of pryuvate. NAD collects the hydrogen ions, forming two reduced NAD. 4 ATP are produced, 2 were used up in stage one so net gain of 2 ATP

Question 14

What are the products of glycolysis (net gain)? (In aerobic respiration)

Answer 14

2 reduced NAD
2 pryuvate
2 ATP (net gain) 4 actually produced but 2 used up in phosphorylation

Question 15

What is pryuvate used for after glycolysis in aerobic respiration?

Answer 15

Actively transported into the mitochondrial matrix for use in the link reaction

Question 16

Where does the produced NAD go after glycolysis?

Answer 16

To oxidative phosphorylation

Question 17

What is pryuvate converted into in anaerobic respiration (in plants and animals) and what is used in this reaction

Answer 17

Plants- ethanol (alcoholic fermentation)
Animals- lactate (lactate fermentation)
Using reduced NAD

Question 18

What is the purpose of lactate or ethanol being produced?

Answer 18

Regenerates oxidised NAD
This means gylcolysis can continue even when there isn’t much oxygen around so ATP can still be produced to keep some biological processes going

Question 19

What happens to pryuvate in the link reaction?

Answer 19

Reaction that converts pryuvate to acetyl coenzyme A. Pryuvate is decarboxylated so one carbon atom is removed from pryuvate in the form of carbon dioxide while simultaneously pryuvate is oxidised to form acetate and NAD is reduced to form reduced NAD.
Acetate is then combined with coenzyme A to form acetyl coenzyme A
No ATP is produced in this reaction

Question 20

What are the products of 2 link reactions?

Answer 20

2 acetyl coenzyme A
2 carbon dioxide
2 reduced NAD

Question 21

Where does the Krebs cycle take place?

Answer 21

In the matrix of the mitochondria

Question 22

What happens in the first stage of the Krebs cycle?

Answer 22

1- Formation of a 6- carbon compound
Acetyl coenzyme A (from the link reaction) combines with 4 carbon molecule (oxaloacetate) to form 6 carbon molecule citrate. Coenzyme A goes back to the link reaction to be used again

Question 23

What happens in the second stage of the Krebs cycle?

Answer 23

1-Formaiton of a 5 carbon compound
Six carbon citrate converted into a 5 carbon molecule by decarboxylation (carbon molecule removed)
Dehydrogenation also occurs. The hydrogen is used to produce reduced NAD from NAD

Question 24

What happens in the final stage of glycolysis?

Answer 24

The regeneration of Oxaloacetate
5 carbon molecule then converted into a 4 carbon molecule
Decarboxylation and dehydrogenation occur producing 1 reduced FAD and 2 Reduced NAD
ATP is produced by the direct transfer of a phosphate group from an intermediate compound to ADP. When phosphate group transferred from molecule to another known as substrate level phosphorylation. Citrate had now been converted into oxaloacetate

Question 25

What are the products of the Krebs cycle?

Answer 25

1 coenzyme A 
Oxaloacetate (4 Carbon compound) 
2 Carbon dioxide
1 ATP 
3 reduced NAD
1 Reduced FAD

Question 26

How much ATP is produced from aerobic respiration?

Answer 26

32

Question 27

What is chemiosmosis?

Answer 27

The process of ATP production moving down the electron transfer chain driven by the movement of H+ ions

Question 28

What is the symbol for protons

Answer 28

H+

Question 29

What is the symbol for electrons?

Answer 29

E-

Question 30

What could happen if aerobic respiration is reduced in animals?

Answer 30

Increase in anaerobic respiration which could cause a lot of lactate being produced which could result in muscle fatigue and weakness