Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOL2520 > Unit 13: Mitochondria and Energy Generation > Flashcards

Unit 13: Mitochondria and Energy Generation Flashcards

(71 cards)

Start Studying
1
Q

what is cellular respiration?

A

breakdown of sugars to release energy

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

what is substrate level phosphorylation?

A

energetically favourable breakdown of a molecule being coupled with the unfavourable process of adding a phosphate to ADP

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

what is oxidative phosphorylation?

A

energy from activated carriers used to drive ATP synthesis

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

50% of the energy in glucose is captured where?

A

in the bonds of ATP

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

how often is all the ATP in a human cell is consumed and replaced?

A

every 1-2 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the first stage of food catabolism? what occurs? WHERE does it occur?

A

digestion.

  • breakdown of large polymers into monomers
  • in intestines and lysosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the second stage of food catabolism? what occurs? WHERE does it occur?

A

glycolysis.

  • one glucose is split into 2 pyruvate, generating 2 NADH and 2 ATP / glucose
  • occurs in cytosol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the intermediate step of food catabolism? what occurs? WHERE does it occur?

A

pyruvate converted to CO2 and acetyl-CoA in mitochondrial matrix

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

what is the third stage of food catabolism? what occurs? WHERE does it occur?

A

citric acid cycle

  • acetyl-CoA oxidized to CO2, generating NADH, ATP, FADH2
  • in mitochondria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how many carbons is glucose? what about pyruvate?

A

6, 3

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

how many ATP do we put in in the investment phase?

A

2

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

how much ATP and NADH do we get out of glycolysis?

A

4 ATP, 2 pyruvate and 2 NADH

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

what is our net gain after glycolysis?

A

2 ATP, 2 pyruvate and 2 NADH

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

what type of phosphorylation occurs in glycolysis?

A

substrate level

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

what do kinases do?

A

add a phosphate group to a molecule

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

what do isomerases do?

A

rearrange bonds within a single molecule

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

what do dehydrogenases do?

A

oxidate molecule via removal of electron/hydrogen

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

what do mutases do?

A

shifting a chemical group from one position to another in a molecule

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

describe step six of glycolysis.

A

oxidation of aldehyde in G3P is coupled with the generation of high energy 1,3-biphosphoglycerate

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

describe step 7 of glycolysis.

A

1,3-biphosphoglycerate is consumed releasing free energy to attach a phosphate to ADP creating ATP

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

what is the free energy change in step 7 of glycolysis?

A

-12.5 kJ/mol

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

what is fermentation?

A

the breakdown of sugars in the absence of oxygen

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

what type of cells undergo fermentation?

A
  • anaerobic microorganisms
  • some animal cells (muscles)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the purpose of fermentation?

A

to regenerate NAD+ to be used in glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is anaerobic respiration?
respiration where a molecule other than oxygen is the terminal acceptor in the ETC
26
how many enzymes form the pyruvate dehydrogenase complex?
3
27
fatty acids break down to what in the intermediate step?
acetyl-CoA
28
what are amino acids converted into in the citric acid cycle?
acetyl-CoA and other intermediates
29
how many carbons are removed from pyruvate to give acetyl-CoA
2
30
what is the aim of the citric acid cycle?
complete oxidation of the acetyl groups in acetyl-CoA by regenerating oxaloacetate
31
acetyl-CoA and oxaloacetate come together to make what?
citric acid
32
how are the oxygen atoms required to make CO2 obtained in the CAC?
from the splitting of H2O
33
what are the products of the CAC/one acetyl-CoA?
- 2CO2 - 1 GTP (becomes ATP) - 3 NADH - 1 FADH2
34
how does the GTP in the CAC become ATP?
the terminal phosphate of GTP is transferred to ADP to make ATP
35
what are control mechanisms?
mechanisms that regulate and coordinate activity of enzymes (enhance/inhibit)
36
what is gluconeogenesis?
reverse of glycolysis, building of glucose from pyruvate
37
how many ATP does gluconeogenesis consume?
4
38
is gluconeogenesis or glycolysis more energetically favourable?
glycolysis
39
can gluconeogenesis and glycolysis occur simultaneously?
no! have to happen one at a time otherwise the cycle will just generate heat and consume energy.
40
can the same enzymes be used in both directions for glycolysis and gluconeogenesis?
some can but not all?
41
describe step three of glycolysis and gluconeogenesis and the different enzymes used.
glycolysis - phosphofructokinase phosphorylates fructose-6-phosphate to produce 1,6-biphosphate gluconeogenesis - fructose 1,6-biphosphatase removes a phosphate group to produce fructose-6-phosphate
42
how is phosphofructokinase activated and inactivated?
activated - ADP, AMP, phosphate inhibited - ATP
43
how is 1,6-biphosphatase activated and inactivated?
activated - ATP inhibited - AMP, ADP, phosphate
44
what is the first stage of oxidative phosphorylation?
ETC
45
what exactly does the ETC do?
transfers electrons between electron carriers to release energy to power pump proteins generating electrochemical proton gradient
46
what does the ETC consume?
O2
47
what si the second stage of oxidative phosphorylation?
chemiosmotic coupling
48
how does chemiosmotic coupling work
protons flow down their electrochemical gradient through ATP synthetase, making large amounts of ATP from ADP and phosphates
49
what can mitochondria do to adjust to the needs of the cell?
change shape (form tubular networks), location and number
50
the outer mitochondrial membrane has many what?
porins
51
describe the inner mitochondrial membrane
- impermeable to most substances - many transport proteins - highly folded into cristae - site of ETC
52
how many proteins does the ETC contain?
40 which form 4 complexes
53
what are the 3 transmembrane complexes in the etc?
- NADH dehydrogenase - cytochrome c reductase - cytochrome c oxidase
54
what acts as stepping stones in the ETC complexes allowing the flow of electrons
metal ions and other chemical groups
55
how much ATP is produced / NADH if it deposits electrons at complex 1
2.5
56
how much ATP is produced / FADH2 if it deposits electrons at complex 2
1.5
57
movement of electrons in the ETC is coupled to what?
pumping of protons across membrane
58
which complexes does complex 1 power? how about complex 2? why?
complex 1 - 2 3 4 complex 2 - 3 4 bc complex 1 is higher up so electrons can move more generating more energy
59
what is the pH in the mitochondrial matrix? how about intermembrane space?
matrix - 7.9 im space - 7.2
60
what is the voltage in the matrix vs intermembrane space?
matrix - negative im space - positive
61
what gradients are present between the mitochondrial matrix and im space?
-pH - voltage - H+
62
what pulls H+ across the membrane?
proton motive force.
63
the greater the membrane potential, the greater ___
the energy stored in proton gradient
64
what causes the confirmational changes allowing for ATP synthesis in the ATP synthase?
movement of the inner stalk pushing the stationary head
65
what generates energy in ATP synthase?
rotation of central stalk
66
describe the structure of ATP synthase
spinning rotor ring embedded in membrane attached to central spinning stalk which is located inside the stationary head
67
how many ATP can ATP synthase produce per revolution?
3
68
how many ATP can ATP synthase produce per second?
100
69
what happens when ATP synthase spins backwards?
consumption of ATP to produce electrochemical gradient when we dont have enough electron carriers
70
when molecules are being brought into the matrix via ATP synthase along with ATP, what is it acting as?
symporter
71
when ATP is being brought out of the mitochondria via ATP synthase, what is it acting as?
antiporter

BIOL2520 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions