2.2 Cellular Respiration Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what is the word equation for aerobic respiration?

A

GO COW

glucose + oxygen –> carbon dioxide + water + energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Purpose of aerobic respiration in cells?

A

to release energy from foods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name the substance to which the energy released from the breakdown of glucose during aerobic respiration is transferred and describe how it is made?

A

ATP

Made from ADP + Pi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are respiratory substrates?

A

Molecules which can be broken down to release energy in respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

This energy released is used to fuel what cellular processes?

A
active transport
muscle contraction
protein synthesis
DNA replication
Carbon fixation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Respiration occurs in the three domains of life, what are these?

A

eukaryotes
bacteria (prokaryotes)
archaea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is ATP? (5)

A

source of immediate energy
means of transferring energy
found in ALL cells
not an enzyme so its not affected by heat
composed of adenosine and three inorganic phosphate molecules to make adenosine triphosphate (ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does the formation of ADP + Pi occur from ATP?

A

The energy held in an ATP molecule is released when the bond attaching the terminal phosphate is broken by enzyme action which results in the formation of adenosine diphosphate (ADP) and inorganic phosphate (Pi)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is needed to regenerate ATP from ADP + Pi?

A

energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is ATP important?

A

because it acts as the link between catabolic energy releasing reactions and anabolic energy consuming reactions.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Example of catabolic energy releasing reactions?

A

respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Example of anabolic energy consuming reactions?

A

protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

CATCHPHRASE

why do you calculating a % change?

A

standardises the results allowing them to be compared

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What enzyme does yeast contain?

A

dehydrogenase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what does enzyme dehydrogenase do?

A

removes hydrogen and high energy electrons from molecules during respiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Loss of hydrogen can be detected how?

A

using resazurin dye which changes colour from blue to pink to colourless as hydrogen is lost from the respiration pathway and added to the dye.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

CATCHPHRASE

purpose of a control

A

Tubes A and C are control tubes for a comparison to prove that the observed results are valid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does resazurin act like in this experiment?

A

acts like a hydrogen acceptor/carrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Why is there only a small amount of ATP present at one point in the body?

A

ATP is constantly being broken down and regenerated very little is stored in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why is compartmentalisation of the inner membrane of a mitochondrion important in terms of metabolic pathways?

A

Compartmentalisation isolates and brings together specific metabolites within a metabolic pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of cell would you find mitochondria?

A

All eukaryotic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are mitochondria?

A

known as powerhouses of the cell, they are the main site of ATP synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does a mitochondria consist of?

A

2 membranes; a smooth outer membrane and a folded inner membrane surrounding a central matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where does the citric acid cycle take place?

A

mitochondria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Where is most ATP generated in?

A

in the electron transport chain which consists of proteins embedded in the inner membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What does the folding of the inner membrane of the membrane form and what does this do?

A

forms cristae increases the membranes surface area, so that more molecules of electron transport chain can fit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is affected if there are more folds and each fold is longer?

A

ATP can be produced faster

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What do active cells contain?

A

lots of large mitochondria with many long cristae e.g sperm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is cell respiration?

A

the breakdown/ oxidation by the removal of hydrogen atoms of glucose molecules within a cell to release energy for the phosphorylation of ADP to ATP.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the three pathways in cell respiration?

A

Glycolysis which occurs in the cytoplasm
Citric Acid Cycle which occurs in the central matrix of the mitochondria
Electron Transport Chain which occurs in the cristae of the mitochondria.

31
Q

Why is glucose called a carbohydrate?

A

Chemical formula is C6H1206 and it contains carbon, hydrogen and oxygen

32
Q

What is glycolysis?

A

a metabolic pathway

33
Q

Is it aerobic or an anaerobic phase?

A

no oxygen is required - anaerobic

34
Q

During glycolysis what happens (brief)?

A

glucose is broken down into pyruvate, there is a net gain of 2ATP

35
Q

What is the energy investment phase?

A

the phosphorylation of intermediates in glycolysis uses 2ATP and is the energy investment phase.

36
Q

What is the phase followed by another phase?

A

followed by reactions that result in the direct regeneration of 4ATP for each glucose molecules and is the energy pay off phase resulting in the net gain of 2ATP

37
Q

What is oxidation?

A

the removal of hydrogen with the release of energy

38
Q

What kind of pathway is respiration?

A

an oxidation pathway

39
Q

What happens during the energy pay-off phase?

A

dehydrogenase enzymes remove hydrogen ions (H+) which combine with the hydrogen carrier NAD to form NADH

40
Q

what happens if oxygen is present?

A

NAD carries hydrogen to the electron transport chain

41
Q

Why is ATP production during glycolysis referred to as a net gain?

A

2 ATP are used in the energy investment phase and 4ATP are produced in the energy pay off phase

42
Q

What is phosphorylation?

A

an enzyme controlled process in which a phosphate group is added to a molecule

43
Q

Where does phosphorylation occur?

A

Occurs in the formation of ADP and Pi
Also occurs when phosphate and energy are transferred from ATP to the molecules of a reactant in a metabolic pathway making them more reactive

44
Q

When will a step in a pathway proceed?

A

proceed only if a reactant becomes phosphorylated and energised

45
Q

during glycolysis what is phosphorylated?

A

phosphorylation of intermediates occur during the energy investment phase

46
Q

State the meaning of fermentation?

A

respiration without oxygen

47
Q

State the location of fermentation in cells?

A

cytoplasm

48
Q

when does anaerobic respiration take place?

A

in the absence of oxygen

49
Q

How many ATP molecules are released by glycolysis in anaerobic respiration?

A

2 ATP molecules

50
Q

What is pyruvate converted to in plant and yeast cells?

A

ethanol and carbon dioxide

51
Q

What is pyruvate converted to in animal cells?

A

lactate

52
Q

Why is anaerobic respiration described as being irreversible?

A

Pyruvate is broken down to ethanol and carbon dioxide is lost to the atmosphere

53
Q

Why is anaerobic respiration in animals described as being reversible and what is it called?

A

Lactate is converted back to pyruvic acid when oxygen becomes available. This is called repaying the oxygen debt.

54
Q

Name the hydrogen carrier in glycolysis?

A

NAD

55
Q

Where does the Citric Acid Cycle (CAC) take place?

A

central matrix of mitochondria

56
Q

What is pyruvate (3C) from GLYCOLYSIS converted to?

A

converted to an Acetyl group (2C) which combines with coenzyme A to form Acetyl Coenzyme A (Acetyl CoA) which enters the CAC.

57
Q

What does dehydrogenase do?

A

removes hydrogen ions which combine with NAD to form NADH

58
Q

What is released?

A

Carbon dioxide (3C –> 2C)

59
Q

What does Acetyl CoA (2C) combine with?

A

oxaloactetate (4C) to form citrate (6C)

60
Q

What is the result of several enzyme controlled steps that occur after?

A

the regeneration of oxaloacetate

61
Q

What is released?

A

Carbon dioxide

62
Q

What is regenerated?

A

ATP from ADP + Pi

63
Q

When more hydrogen is released what does it combine with?

A

with NAD to form NADH and a second coenzyme FAD to form FADH2

64
Q

What is the optimum function of respiratory enzymes such as dehydrogenase and optimum production of ATP?

A

human body temp 37 degrees

65
Q

Why will the CAC go round twice for each glucose molecule?

A

there are two pyruvate molecules at the end of glycolysis

66
Q

Describe the role of dehydrogenase in glycolysis and CAC?

A

oxidises and removes hydrogen ions from metabolites which are carried by NAD and FAD to the electron transport chain

67
Q

Why is the inner mitochondrial membrane highly folded?

A

to increase the surface area over which the reactions of the electron transport chain can occur maintaining a high reaction rate.

68
Q

Where does the Electron Transport Chain (ETC) take place?

A

on the cristae (inner folded membrane) of the mitochondrion

69
Q

Explain the process?

A

chain of protein carrier molecules accept high energy electrons from the hydrogen carriers NADH and FADH2

High energy electrons flow along the chain of protein carrier molecules

Energy released from this flow of electrons is used to pump hydrogen ions across the inner membrane of the mitochondria from the matrix side to the space between the membranes

The return flow of H ions back to the matrix rotates part of a membrane protein called ATP synthase which synthesises ATP to form ADP + Pi

When the low energy H ions and electrons reach the end of the protein carrier chain they combine with oxygen which is the final hydrogen acceptor to form water.

70
Q

How will the H+ ions move back into the matrix?

A

diffusion

71
Q

What will they require?

A

channel proteins/ pores

72
Q

Why do we need to breathe in every 5 seconds?

A

to provide oxygen as the final hydrogen acceptor in the ETC

73
Q

What does cyanide do?

A

Inhibits the enzyme in the ETC which stops the flow of electrons

74
Q

what happens to the rest of the energy in anaerobic respiration?

A

glucose isnt completely broken down to release all the energy therefore the energy is held in the bonds of lactate in mammals and ethanol in plants/yeast