2.8 Cell respiration

Question 1

What is cell respiration?

Answer 1

The controlled release of energy from organic compounds to produce ATP

Question 2

What is the main organic compound used in cell respiration?

Answer 2

Carbohydrates (glucose)

Question 3

Alongside carbohydrates what else is digested during cell respiration?

Answer 3

Lipids and proteins

Question 4

What are the two types of cell respiration?

Answer 4

Anaerobic respiration and aerobic respiration

Question 5

What does anaerobic respiration involves?

Answer 5

It involves the partial breakdown of glucose in the cytosol for a small yield of ATP

Question 6

What does aerobic respiration utilise to do what?

Answer 6

Oxygen to break down glucose in the mitochondria for a larger ATP yield

Question 7

What is the cell respiration equation?

Answer 7

Glucose + oxygen = carbon dioxide + water + atp

Question 8

What does ATP stand for?

Answer 8

Adenosine triphosphate

Question 9

What is ATP?

Answer 9

A high energy molecule that functions as an immediate source of power for cell processes

Question 10

What does one molecule of ATP contain?

Answer 10

Three covalently linked phosphate groups

Question 11

What does the three covalently linked phosphate groups do?

Answer 11

Store potential energy in their bonds

Question 12

What happens when ATP is hydrolysed?

Answer 12

The energy stored in the phosphate bond is released to be used by the cell

Question 13

What does cell respiration use energy from organic molecules to do?

Answer 13

Regenerate ATP from ADP + Pi

Question 14

What do both anaerobic and aerobic respiration pathways begin with?

Answer 14

The anaerobic breakdown of glucose in the cytosol

Question 15

What is responsible for the anaerobic breakdown of glucose in the cytosol?

Answer 15

Glycolysis

Question 16

What does glycolysis break down and into what?

Answer 16

Glucose into two molecules of pryuvate

Question 17

What else does pryuvate produce?

Answer 17

Hydrogen carriers from an oxidised precursor

A small yield of ATP

Question 18

When does anaerobic respiration proceed?

Answer 18

In the absence of oxygen

Question 19

What does anaerobic respiration not result in?

Answer 19

The production of any further ATP molecules

Question 20

What is pyruvate converted into in animals?

Answer 20

Lactic acid (lactate)

Question 21

What is pyruvate converted into in plants and yeasts?

Answer 21

Ethanol and carbon dioxide

Question 22

What is the purpose of anaerobic respiration?

Answer 22

To restore stocks of NAD+

Question 23

Why does anaerobic respiration restore stocks of NAD+?

Answer 23

So the organism can continue producing ATP via glycolysis

Question 24

Is the conversion of pyruvate in animals/plants and yeast reversible?

Answer 24

Yes

Question 25

What can be restored once oxygen is present?

Answer 25

Pyruvate levels

Question 26

Why does muscle contractions require high levels of ATP?

Answer 26

Because the expend high amounts of energy

Question 27

What happens to the cells energy demands when exercising at high intenisty?

Answer 27

They will exceed what the available levels of O2 can supply aerobically

Question 28

When exercising at high intensity what does the body do to maximise ATP production?

Answer 28

Begin to break down glucose anaerobically

Question 29

What leads to muscle fatigue?

Answer 29

An increase in the production of lactic acid

Question 30

What happens when an individual stops exercising?

Answer 30

Oxygen levels will increase and lactate will be converted back to pyruvate

Question 31

What can only be used to undergo anaerobic respiration?

Answer 31

Carbohydrates

Question 32

When talking about exercise intensity, when will lactate levels increase?

Answer 32

At higher levels of exercise intensity

Question 33

When talking about exercise intensity, what happens to the aerobic consumption of fats at high intensities?

Answer 33

It decreases

Question 34

When talking about exercise intensity, what happens to the anaerobic consumption of sugars at high intensities?

Answer 34

It increases

Question 35

Where does aerobic cell respiration take place?

Answer 35

In the mitochondrion

Question 36

What does aerobic cell respiration require the presence of?

Answer 36

Oxygen

Question 37

During aerobic respiration what is pyruvate broken down into?

Answer 37

Carbon dioxide and water

Question 38

During aerobic respiration, what is produced and how much?

Answer 38

ATP (34 - 36 molecules)

Question 39

What type of process is glycolysis?

Answer 39

Anaerobic

Question 40

What does aerobic respiration consist of?

Answer 40

The link reaction, krebs cycle and the electron transport chain

Question 41

Where does aerobic respiration begin?

Answer 41

With glycolysis in carbohydrates

Question 42

What does fermentation involve?

Answer 42

The breakdown of carbohydrates in the absence of oxygen

Question 43

In yeasts what does fermentation results in the production of?

Answer 43

Ethanol and carbon dioxide

Question 44

What is used during food processesing?

Answer 44

Fermentation in yeasts

Question 45

How is yeast fermentation used in bread?

Answer 45

Carbon dioxide causes dough to rise The ethanol evaporates during baking

Question 46

How is yeast fermentation used in alcohol?

Answer 46

Ethanol is the intoxicating agent in alcoholic drinks

Question 47

What do bacterial cultures undergo to produce food products?

Answer 47

Fermentation

Question 48

How are bacterial cultures used in yogurt and cheese?

Answer 48

Bacteria produces lactic acid anaerobically which modifies milk proteins to make yogurts and cheeses

Question 49

What is a respirometer?

Answer 49

A device that determines an organisms respiration rate by measuring the rate of exchange of oxygen and carbon dioxide

Question 50

What factors affect respiration rates?

Answer 50

Temperature Hydration Light Age Activity levels

Question 51

How does an increase in carbon dioxide levels affect respiration and why?

Answer 51

Increases respiration as carbon dioxide is a product of aerobic respiration

Question 52

How does a decrease in oxygen levels affect respiration and why?

Answer 52

Increases respiration as oxygen is a requirement of aerobic respiration

Question 53

How does a respirometer work?

Answer 53

The living specimen is enclosed in a sealed container

Question 54

How can carbon dioxide production be measured in respirometer?

Answer 54

With a data logger or by pH changes if the specimen is in water

Question 55

When can oxygen consumption be measured as a change in pressure within the system?

Answer 55

When an alkali is included to absorb carbon dioxide

Question 56

How can pressure change be detected in a respirometer?

Answer 56

With a data logger or via use of a u-tube manometer