Topic 5— A: Photosynthesis and Respiration- 6. Aerobic and Anaerobic respiration

Question 1

How can respiration be done?

Answer 1

Aerobically (with oxygen) or Anaerobically (without oxygen)

Question 2

Which type of respiration produces less ATP?

Answer 2

Anaerobic respiration

Question 3

Where do the reactions in aerobic respiration occur?

Answer 3

In the mitochondria

Question 4

What do the folds (cristae) in the inner membrane of the mitochondria provide?

Answer 4

A larger surface area to maximise respiration

Question 5

What is a coenzyme?

Answer 5

It’s a molecule that aids the function of an enzyme by transferring a chemical group from one molecule to another

Question 6

How to coenzymes aid the function of an enzyme?

Answer 6

• By transferring a chemical group from one molecule to another

Question 7

Examples of coenzymes used in respiration

Answer 7

• NAD
• Coenzyme A
• FAD

Question 8

What do NAD and FAD do?

Answer 8

-They transfer hydrogen from one molecule to another.

Question 9

What does coenzyme A do?

Answer 9

It transfers acetate between molecules.

Question 10

What does it mean when NAD and FAD can reduce?

Answer 10

• Give hydrogen to
• Reduced NAD is NADH

Question 11

What does it mean when NAD and FAD can oxidise?

Answer 11

• Take hydrogen from a molecule

Question 12

What are the four stages in aerobic respiration?

Answer 12

1. Glycolysis
2. Link reaction
3. Krebs cycle
4. Oxidative phosphorylation

Question 13

What are the first 3 stages in the cycle?

Answer 13

• They are a series of reactions
• The products from these reactions are used in the final stage to produce lots of ATP.

Question 14

Where does glycolysis occur?

Answer 14

In the cytoplasm of cells

Question 15

What does anaerobic respiration not involve?

Answer 15

• The link reaction, krebs cycle, oxidative phosphorylation
• Products of glycolysis are converted to ethanol or lactate instead of

Question 16

Glycolysis

Answer 16

• Makes pyruvate from glucose
• Involves splitting one molecule of glucose (6c) into 2 smaller molecules of pyruvate (3c)
• Anaerobic process as it doesn’t need oxygen to take place

Question 17

Stages in glycolysis

Answer 17

1. Phosphorylation- glucose is phosphorylated using a phosphate from a molecule of ATP.
   - This creates 1 molecule of glucose phosphate and 1 molecule of ADP.
   - ATP is then used to add another phosphate, forming glucose bi phosphate
   - Glucose bi phosphate is then split into 2 molecules of triose phosphate
2. Oxidation
   -triose phosphate is oxidised (loses hydrogen) forming 2 molecules of pyruvate.
   - NAD collects the hydrogen ions forming NADH.

Question 18

Products of glycolysis

Answer 18

• 2 reduced NAD
• 2 pyruvate
• 2 ATP (net gain)

Question 19

What happens with the pyruvate produced in glycolysis in anaerobic respiration?

Answer 19

• pyruvate is converted into ethanol (alcoholic fermentation) or lactate (lactate fermentation) using reduced NAD.

Question 20

Where does alcoholic fermentation occur?

Answer 20

• plants and yeast

Question 21

Where does lactate fermentation occur?

Answer 21

• animal cells and some bacteria

Question 22

What does the production of lactate or ethanol regenerate?

Answer 22

oxidised NAD

Question 23

What does it mean when oxidised NAD is regenerated in glycolysis?

Answer 23

• Glycolysis can continue even when there isn’t much oxygen around so a small amount of ATP can still be produced to keep some biological processes going

Question 24

If there is oxygen, what will happen to Pyruvate?

Answer 24

It will enter the link reaction

Question 25

If there is no oxygen, what will happen to Pyruvate?

Answer 25

It will follow anaerobic respiration so products of glycolysis will be converted into ethanol/ lactate

Question 26

Phosphorylation

Answer 26

process of adding a phosphate group to a molecule