Respiration

Question 1

What is aerobic respiration?

Answer 1

• The complete breakdown of glucose to form carbon dioxide and lots of ATP- Requires oxygen- Slow- More ATP produced per molecule of glucose than in anaeobic

Question 2

What is anaerobic respiration?

Answer 2

• The incomplete breakdown of glucose to form harmful products such as lactic acid in animals and bacteria and ethanol in plants and yeast - Doesn’t need oxygen- Fast

Question 3

Where does glycolysis take place?

Answer 3

In the cytoplasm

Question 4

Is glycolysis aerobic or anaerobic?

Answer 4

Anaerobic

Question 5

What are the net products of glycolysis?

Answer 5

• 2 ATP- 2 NADP- 2 Pyruvate

Question 6

What happens to glucose in glycolysis?

Answer 6

It is phosphorylated by adding a phosphate from ATP

Question 7

What is glucose phosphorylated to in glycolysis?

Answer 7

Glucose phosphate

Question 8

What happens to glucose phosphorylate in glycolysis?

Answer 8

It is phosphorylated by adding a phosphate from ATP

Question 9

What is glucose phosphate phosphorylated to in glycolysis?

Answer 9

Hexose Bisphosphate

Question 10

What happens to hexose bisphosphate in glycolysis?

Answer 10

It splits (due to its reactivity) into two triose phosphate molecules

Question 11

What happens to each triose phosphate molecule in glycolysis?

Answer 11

They are oxidised to form pyruvate

Question 12

When are the products of glycolysis produced?

Answer 12

During the oxidation of triose phosphate to pyruvate

Question 13

What is the organic product of glycolysis?

Answer 13

Pyruvate

Question 14

Where does the link reaction take place?

Answer 14

Inside the matrix of the mitochondria

Question 15

What are the products of the link reaction per reaction?

Answer 15

1 CO2, 1 NADH

Question 16

What are the products of the link reaction per glucose?

Answer 16

2 CO2, 2NADH

Question 17

What is dehydrogenation?

Answer 17

Loss of a hydrogen atom or ion

Question 18

What is decarboxylation?

Answer 18

Loss of a carbon atom

Question 19

What happens to pyruvate in the link reaction?

Answer 19

It is dehydrogenated and decarboxylated to form acetate

Question 20

What happens to the hydrogen removed from the pyruvate during the link reaction?

Answer 20

It reduces a molecule of NAD to NADH

Question 21

What happens to the carbon removed from the pyruvate during the link reaction?

Answer 21

It combines with oxygen to form carbon dioxide which is a product of respiration

Question 22

What happens to the acetate obtained from pyruvate?

Answer 22

It combines with coenzyme A to form acetyl coenzyme A

Question 23

Where does the krebs cycle take place?

Answer 23

In the matrix of a mitochondria

Question 24

What happens do acetyl coenzyme a in the krebs cycle?

Answer 24

It joins a 4 carbon compound to form a 6 carbon compound

Question 25

What happens to coenzyme A after acetate has been used to form a 6 carbon compound? (krebs)

Answer 25

It is recycled back to the link reaction

Question 26

What happens to the 6 carbon compound? (krebs)

Answer 26

It is decarboxylated and dehydrogenated to form a 5 carbon compound- Decarboxylation produces carbon dioxide as a waste product- Dehydrogenation reduces NAD to NADH

Question 27

What happens to the 5 carbon compound? (krebs)

Answer 27

- Decarboxylation- Reduction (2NAD to 2NADH + FAD to FADH)- Substrate level phosphorylation

Question 28

What is substate level phosphorylation?

Answer 28

Creation of ATP without ATP synthase, phosphate is added to ADP from another molecule

Question 29

What happens to the 4 carbon compound after substate level phosphorylation?

Answer 29

It goes to the start of the cycle to combine with acettate from acetyl coenzyme A

Question 30

How can lipids and proteins be respired aerobically?

Answer 30

They are broken down into acetyl coenzyme A to enter the krebs cycle

Question 31

What are the products of the krebs cycle per cycle?

Answer 31

- 3 x NADH- 1 x ATP - 1 x FADH- 2 x CO2

Question 32

What is the first step in oxidative phosphorylation?

Answer 32

NADH and FADH are oxidised to release electrons and protons

Question 33

What happens once electrons are released from coenzymes? (oxidative phosphorylation)

Answer 33

Electrons flow along an electron transport chain in a series of redox reactions

Question 34

What happens to the energy released from electrons passing down the electron transport chain? (oxidative phosphorylation)

Answer 34

Electrons release energy which is used to join ADP and Pi

Question 35

What is the final electron acceptor? (aerobic respiration)

Answer 35

Oxygen, it combines with electrons and protons to form water

Question 36

Which stage of respiration produces the most ATP in aerobic respiration?

Answer 36

Oxidative phosphorylation

Question 37

Where does glycolysis take place?

Answer 37

In the cytoplasm

Question 38

Which type of respiration is the more efficient producer of ATP?

Answer 38

Aerobic respiration

Question 39

What happens in anaerobic respiration?

Answer 39

- Glycolysis takes place and then pyruvate is further used to oxidise NADH to NAD which is then re used in glycolysis

Question 40

Why does anaerobic respiration happen?

Answer 40

NAD needs to be regenerated

Question 41

What is produced in anaerobic respiration in mammals and bacteria?

Answer 41

Lactate (lactose fermentation)

Question 42

What is produced in anaerobic respiration in yeasts and plants?

Answer 42

Ethanal which is then reduced to ethanol (alcoholic fermentation)

Question 43

Does anaerobic respiration produce more or less ATP that aerobic?

Answer 43

Anaerobic respiration produces less ATP because lactate/ethanol aren't fully respired (still have chemical energy)

Question 44

What doesn't anaerobic respiration have?

Answer 44

Oxygen as a final electron acceptor

Question 45

What is a respiratory substrate?

Answer 45

Any biological molecule that can be respired to release energy

Question 46

What are three respiratory substrates?

Answer 46

- Carbohydrates- Lipids- Proteins

Question 47

Why does every cell respire?

Answer 47

Respiration is essential life because ATP is needed for all metabolic processes (e.g. active transport), cells also need to produce the minimum amount of ATP needed to maintain metabolism

Question 48

Which respiratory substate has the most energy per gram?

Answer 48

Lipids > Proteins > Carbohydrates

Question 49

Which respiratory substate is used last?

Answer 49

Protein is only respired when there's no lipids or carbohydrates

Question 50

What is the mitochondria?

Answer 50

The site of aerobic respiration in a eukaryote

Question 51

What makes up a mitochondria?

Answer 51

- Mitochondrial DNA- Matrix- Cristae- Inner membrane- Outer membrane

Question 52

What is the matrix of a mitochondria?

Answer 52

Site of the link reaction and the krebs cycle

Question 53

What is the cristae of a mitochondria?

Answer 53

- A fold in the inner membrane of the mitochondria- Increases the surface area for oxidative phosphorylation