Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

LIFE 122 > Respiration(Week 2&3) > Flashcards

Respiration(Week 2&3) Flashcards

1
Q

Give the equation for respiration.

A

C6H12O6 + 6O2 = 6CO2 + 6H2O

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

How many separate reactions occur in glycolysis?

A

10

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

What is the net gain of ATP during hydrolysis?

A

2

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

The first three steps of glycolysis are called the…

A

Preparatory phase. Energy investment to be recovered later

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

The fourth and fifth step of glycolysis are called…

A

The cleavage stage. 6C compound into 2x3C sugars

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

The last five steps of glycolysis is are called…

A

The pay off stage, where energy is generated

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

What happens during step one of glycolysis. What are the enzymes and intermediates?

A

Glucose of phosphorylated to glucose-6-phosphate by the enzyme hexokinase. This required one molecule of ATP.

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

What happens in step 2 of glycolysis? What are the enzymes and intermediates?

A

Glucose-6-phosphate becomes Fructose-6-phosphate as the carbonyl oxygen moved from C1 to C2 to become a more symmetrical molecule.

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

What happens during step 3 of glycolysis. What are the enzymes and intermediates involved?

A

Fructose-6-phosphate phosphorylates the C1 giving fructose-1,6-biphosphate. This uses one ATP and the Phospho-fructokinase-1 enzyme

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

What happens during step 4 of glycolysis. What are the enzymes and intermediates involved?

A

Fructose-1,6-bisphosphate is cleaved into two three carbon molecules, dihydroxyacetone phosphate and glyceraldehyde-3-phosphate.

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

What happens during step 5 of glycolysis. What are the enzymes and intermediates involved?

A

Dihydroxyacetone phosphate is converted into glyceraldehyde-3-phosphate by switching the positions of the C-OH and the C=O

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

What happens during step 6 of glycolysis. What are the enzymes and intermediates involved?

A

Glyceraldehyde-3-phosphate is oxidised and phosphorylated to form 1,3-bisphosphoglycerate

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

What happens during step 7 of glycolysis. What are the enzymes and intermediates involved?

A

1,3-bisphosphoglyceraye is converted to 3-Phosphoglycerate. This forms 1xATP

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

What happens during step 8 of glycolysis. What are the enzymes and intermediates involved?

A

3-Phosphoglycerate becomes 2-Phosphoglycerate in order to release more energy when the phosphate is removed.

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

What happens during step 9 of glycolysis. What are the enzymes and intermediates involved?

A

The 2-Phosphoglycerate then becomes Phosphoenolpyruvate by removing the OH group

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

What happens during step 10 of glycolysis. What are the enzymes and intermediates involved?

A

Phosphenolpyruvate then becomes pyruvate when the phosphate group joins onto an ADP molecule to become ATP

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

What are the intermediates of glycolysis?

A

Glucose, Glucose-6-phosphate, Fructose-6-phosphate, Fructose biphosphate, dihydroxyacetone phosphate, G, 1,3-bisphosphoglycerate, P, P, Phosphoenolpyruvate, Pyruvate

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

How is glycolysis inhibited?

A

The enzyme hexokinase is inhibited by glucose 6-phosphate.
Also, high levels of ATP inhibit glycolysis as glycolysis doesn’t need to occur if there are already lots of ATP.
Phosphofructokinase is also a key regulator also as ATP binds and alters its shape.

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

What is gluconeogenesis?

A

A multi step process in which pyruvate, is used to make glucose. 7 of the steps from glycolysis can just be reversed using the same enzymes. However there are three irreversible steps (1, 3, and 10) which must be bypassed

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

Which steps in glycolysis are irreversible?

A

1, 3, 10

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

When Pyruvate leaves glycolysis, its fate depends on the concentration of what molecule?

A

Oxygen

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

In the absence of Oxygen for the citric acid cycle, glycolysis couples with fermentation in order to regenerate NAD+ to be able to produce ATP by glycolysis. What are the two types of fermentation?

A

Alcohol

Lactic acid

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

Describe the process of alcohol fermentation.

A

Pyruvate looses a CO2, so is converted to acetaldehyde, which is then reduced and forms ethanol.

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

Describe the process of lactic acid fermentation.

A

Pyruvate itself acts as the end point acceptor for the electrons and is reduced to form lactate.
Produces Lactate and NAD+

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

How many ATPs are produced by aerobic and anaerobic respiration respectively?

A

38

2

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

In an oxygen rich cell, what is Pyruvate oxidised to, in the mitochondria?

A

Acetyl-CoA

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

The oxidation of Pyruvate to Acety-CoA is catalysed by…

A

A large multienzyme complex made up of multiple copies of different enzymes. (Pyruvate dehydrogenase most common)

28
Q

In the pyruvate dehydrogenase complex, what are the four vital vitamins?

A

B1 (Thiamine)
B2 (Riboflavin)
B3 (Niacin)
B5 (Pantothenate)

29
Q

Describe step 1 in the citric acid cycle.

A

Condensation
Catalysed by the citrate synthase enzyme.
Oxoloacetate (4C) + Acetyl CoA (2C) = Citrate (6C)

30
Q

Describe step 2 of the citric acid cycle.

A

Dehydration followed by hydration.
Catalysed by aconitine.
Citrate is a tertiary alcohol, so does not release a lot of energy when oxidised. So the OH group is removed and then replaces and this creased isocitrate which is a secondary alcohol.

31
Q

Describe step 3 of the citric acid cycle.

A

Oxidative decarboxylation.
Catalysed by isocitrate dehydrogenase
This produces one molecule of CO2 and NAD+ which acts as an electron acceptor and one molecule of NADH is produced
(6C to 5C)

32
Q

Describe step 4 of the citric acid cycle

A

Oxidative decarboxylation.
Catalysed by the alphaketoglutarate dehydrogenase complex.
This produces one molecule of CO2, and another NAD+ which again acts as an electron acceptor giving one molecule of NADH.
(5C to 4C)

33
Q

Describe step 5 of the citric acid cycle

A

Substrate level phosphorylation
Catalysed by Succinylcholine Co-A synthase.
This happens in two steps. First, the Pi displaces the CoA producing succinyl phosphate. The phosphoryl group is then transferred to GDP. This leaves succinct enough and GTP.
This GTP can be converted to ATP

34
Q

Describe step 6 of the citric acid cycle

A

Dehydrogenation
Catalysed by succinct dehydrogenase.
Succinct enough is dehydrogenase by the enzyme whose electron acceptor is FAD. This form fumaraye and FADH2

35
Q

Describe step 7 of the citric acid cycle

A

Hydration

Catalysed by Fumarase

36
Q

Describe step 8 of the citric acid cycle.

A

Dehydrogenation.
Catalysed by manate dehydrogenase
NAD+ acts as an electron acceptor and one molecule of NADH is produced

37
Q

Name the products from one turn of the citric acid cycle.

A 
3xNADH
2xCO2
1xGTP (ATP)
1xFADH2
REMEMBER: De NAD, De NAD, A, FAD, NAD
38
Q

Name the intermediates of the citric acid cycle

A 
Acetyl Co-A
Citrate
Isocitrate
Alphaketoglutarate
Succinyl-Co-A
Succinate
Fumarate
Malate
Oxaloacetate
39
Q

The citric acid cycle is amphibolic. What does this mean?

A

The intermediates of the cycle can be drawn off and used as the starting material for other biosynthetic products.

40
Q

How is the citric acid cycle regulated?

A

It is controlled by the rate of conversion of pyruvate to Acetyl CoA and the rate of the activity of the enzymes at the start of the CA cycle.

41
Q

Under what circumstances would the PHD complex be inhibited?

A

When ATP, NADH and Acetyl-Co-A levels are high

42
Q

What factors effect the rate of flow through the cycle.

A

The availability of oxaloacetate, Acetyl CoA and NAD+ which is depleted by its conversion to NADH

43
Q

In muscle tissue, what ion stimulates the energy producing metabolism to replace ATP consumed by contraction.

A

Ca2+

44
Q

Give an overview of the steps involved in oxidative phosphorylation (ETC).

A 
Complex 1 (NADH dehydrogenase)
Q (Ubiquinone)
Complex 2 (succinate dehydrogenase)
Complex 3 (Cytochrome c oxidoreductase)
Cytochrome C
Complex 4 (Cyrocheome oxidase)
45
Q

Describe the structure of the cytochromes.

A

They contain a bound heme group, of an iron atom which changes from Fe3+ to Fe2+ whenever it accepts an electron. The heme group consists of a porphyria ring with a tightly bound iron atom help in the centre by four nitrogen’s.

46
Q

Describe the structure of the iron soulful proteins.

A

The iron is present in association with the inorganic sulfur atoms or with the sulfur atoms of cysteine residues in the protein. These centres can contain 1, 2 or 4 iron atoms.

47
Q

Describe the structure of ubiquinone.

A

Small hydrophobic molecule which is mobile in the bilayer. It can pick up or donate one or two electrons. When reduced it picks up a proton from the medium along with each electron it carries.

48
Q

How is H+ pumped along the membrane?

A

Ubiquinone picks up electrons from the transport chain and protons from the matrix. The reduced Ubiquinone diffuses to the opposite face of the membrane where is passes the electrons on to other carriers in the chain and loses protons to the intermembrane space.

49
Q

What is the use of oxygen in the ECT.

A

ROS (reactive oxygen species) are the terminal electron acceptors as they have a high affinity for electrons causing a high thermodynamic driving force. However, this can cause problems as the transfer of four electrons forms a safe product, however, the partial reduction causes the formation of peroxide’s which can be dangerous.

50
Q

How does the flow of protons generate ATP?

A

The flow of H+ into the matrix down its concentration gradient causes the F0 and the central stalk to rotate. The catalytic F1 domain is held by the peripheral stalks. The rotating stalk pushes the catalytic beta subunits of F1 into different conformations and interacts with them in turn.

51
Q

Describe stage one of fatty acid oxidation.

A

Oxidative conversion of two carbon subunits into Acetyl Co-A, which is accompanied by the generation of NADH and FADH2

52
Q

Describe stage two of fatty acid oxidation.

A

Stage 2 involves the oxidation of Acetyl-CoA via the citric acid cycle which also generates NADH and FADH2

53
Q

Describe stage three of fatty acid oxidation.

A

Electrons are transferred from NADH and FADH2 to O2, and energy is released and used to produce ATP from ADP and Pi

54
Q

Where does beta oxidation of fatty acids occur.

A

The mitochondrial matrix.
Small fatty acids of less than 12 carbons can diffuse freely across the membrane, whilst larger ones are transported via the acyl-carnitine transporter.

55
Q

Describe step one of beta oxidation.

A

Dehydrogenation.
Palmitoyl-CoA is converted to Enoyl-CoA using the enzyme amylase-CoA dehydrogenase. FAD acts as an electron acceptor so FADH2 is produced.

56
Q

Describe step 2 of beta oxidation

A

Hydration
Enoyl-CoA is converted to beta-Hydroxy-amylase-CoA as a molecule of H2O is added. This I’d completed using the enzyme enoyl-CoA hydratase

57
Q

Describe step 3 of beta oxidation

A

Beta-hydroxy-amylase-CoA is converted to beta-Ketoacyl-CoA using the enzyme beta-hydroxyacyl-CoA dehydrogenase. Two electrons are removed so NADH+ is formed.

58
Q

Describe step 4 of the beta oxidation

A

Thiolysis

Beta-Ketoacyl-CoA is converted to acetyl-CoA using the acetylene-CoA acetyltransferase enzyme.

59
Q

In excess what can glucose be stored as and why?

A

Stores as fat because fatty acids can be synthesised from acetyl-CoA

60
Q

Fatty acids cannot be converted to… and why?

A

Glucose

Because acetyl CoA can’t be converted into pyruvate.

61
Q

Pyruvate to acetyl co a…

A

Occurs in the mitochondria

Required several B vitamins

62
Q

Glycolysis produces ATP by…

A

Substrate level phosphorylation

63
Q

Describe oxidative phosphorylation

A

Electrons from NADH and FADH2 are passed through a chain of electron carriers to Oxygen which is reduced to form water. The energy released pumps protons across the inner mitochondrial membrane. Protons flow back into the matrix via ATP synthase and allows ATP to be formed from ADP and Pi

64
Q

In the ETC

A

The electrochemical proton gradient consists of a pH difference and an electrical potential.
The ETC generated an electron potential across the inner mitochondrial membrane because it pumps protons into the matrix.
Ubiquinone and cytochrome C are diffusable electron carriers

65
Q

LDLs can…

A

Carry cholesterol to peripheral tissues

Have a higher protein content than chylomicrons

LIFE 122 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions