Brainscape's Knowledge GenomeTM

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


See full index

Biochemistry 2 > Tissue Specific Metabolism > Flashcards

Tissue Specific Metabolism Flashcards

1
Q

What is neuronal signaling? How far do the neurotransmitters travel to their target cells?

A

Nerve impulses from the cell body of a neuron travel to the axon tip. Here neurotransmitters are released and travel to the target cell a fraction of a micrometer away.

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

What is endocrine signaling? How far do the neurotransmitters travel to their target cells?

A

Hormones are secreted into the bloodstream, which carries them through the body to target tissues that may be a meter or more away!

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

What are hormones produced by?

A

Endocrine glands

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

What are the 8 major endocrine glands?

A

Hypothalamus, pituitary, thyroid, adipose tissue, adrenals, pancreas, ovaries, testes

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

Which two endocrine glands make the regulatory hormones that regulate all other endocrine glands?

A

Hypothalamus and pituitary glands

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

Which two endocrine glands are connected through special blood vessels and neurons?

A

Pituitary and hypothalamus

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

Where are the adrenal glands located?

A

Above kidneys

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

What does the pancreas release?

A

Insulin and glucagon

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

What do the adipose tissues release?

A

Leptin, adiponectin, etc.

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

What do the pituitary glands produce as a response to hypothalamic hormones carried in the blood?

A

Tropic hormones that activate the other endocrine glands

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

Once the central nervous system releases a hormonal signal to the hypothalamus, what is special about the final product of the signalling cascade?

A

The end product negatively regulates (inhibits) its own production.

Makes sense: once it is produced enough and has done its job, not needed anymore.

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

What 3 nutrients do hepatocytes metabolize?

A

COH, AA, lipids

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

What is the function of hepatocytes?

A

Transform dietary nutrients into precursors required by other tissues and exports them via the blood.

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

What does the liver maintain the balance between?

A

Nutrient supply and precursor demand.

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

What does nutrient supply vary with? what does precursor requirement vary with? (In the liver)

A

Nutrient supply: diet and feeding

Precursor requirement: level of activity and health

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

Which hormones are liver enzymes sensitive to?

A

Insulin, glucagon, epinephrin, leptin

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

What does this statement mean: the liver has remarkable flexibility in “enzymatic machinery”?

A

That the liver synthesizes enzymes based off of the nutrients present in the body that need to be metabolized.

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

Transport of glucose in and out of the liver via the blood stream is done by what transporter? What type of transport is this?

A

GLUT2. Passive transport

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

What is hexokinase 4’s affinity for glucose?

A

Very low (high Km)

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

Is hexokinase inhibited by G6P?

A

No

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

When G6P undergoes glycolysis and is converted to pyruvate then acetyl CoA, what path does it mainly take afterwards?

A

Mainly gets turned into FA/cholesterol. It is more rare for Acetyl-CoA to go through TCA cycle

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

AA metabolism in the liver yields proteins for what?

A

For the liver and other tissues

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

What are some of the AAs in the liver precursors of?

A

Nucleotides & hormones

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

The AAs in the liver not needed as biosynthetic precursors are turned into what?

A

Transaminated or deaminated into pyruvate and TCA intermediates

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

For what two reasons is pyruvate sometimes converted to acetyl-CoA in the liver?

A
  1. liver cell energy

2. conversion to lipids

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

Once AAs have been converted into pyruvate in the liver, what are the 2 fates it can take?

A

Gluconeogenesis

Acetyl-CoA

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

Why can the liver be referred to as an endocrine gland?

A

Because it stimulates insulin-like-growth-factors (IGF(IDF?)-1 and IGF(IDF?)-2)

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

What is the main fate of lipids in the liver?

A

They undergo Beta-oxidation which yeilds NADH and acetyl-CoA for TCA cycle –> to make energy for hepatocytes

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

What 2 paths might the excess acetyl-CoA that does not enter the TCA cycle in the liver? c

A
  1. It is converted to ketone bodies that are sent to heart and brain.
  2. biosynthesis of cholesterol (required for membrane synthesis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is cholesterol a precursor of?

A

Bile salts and all steroid hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the main lipo-proteins released from the liver?

A

VLDL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What are non-esterified free fatty acids that leave the liver bound to? Where do they go?

A

Albumin –> heart and skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What nutrients does the liver store?

A

Iron and Vitamin A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Where are white adipose tissues located?

A

Under skin, around major blood vessels and abdomen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How many lipid droplets do the adipocyte cells contain in white adipose tissues?

A

1 lipid droplet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the energy source of white adipose tissue?

A

glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are white adipose tissues sensitive to? They are capable of synthesis of what from glucose?

A

Insulin sensitive. Capable of FA synthesis from glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What is the major storage of white adipose tissues?

A

TAG

39
Q

What do white adipose tissues do when the demand for fuel rises? (between meals, for example). What is this greatly accelerated by?

A

lipases and adipocytes hydrolyze stored TAGs to release (non-esterified) free fatty acids, which can travel in the blood stream to muscle and heart. Greatly accelerated by epinephrine

40
Q

Where is Brown Adipose Tissue located?

A

Under skin (chest and back)

41
Q

In what age range in Brown Adipose Tissue found?

A

Only in infants

42
Q

What is high in concentration in Brown Adipose Tissue?

A

Mitochondria, blood supply

43
Q

How are TAGs stored in Brown Adipose Tissue compared to White Adipose Tissue?

A

Many small lipid droplets per cell

44
Q

How do fatty acids undergo complete conversion to CO2 in Brown Adipose Tissue?

A

FAs stored in lipid droplets are released, enter mitochondria, and go through Beta-oxidation and the TCA cycle

45
Q

What gene is strongly expressed in Brown Adipose Tissue? What does this gene encode for? What inhibits/activates this gene?

A

UCP-1.

Codes from thermogenin which is the protein that allows H+ to bypass ATPase in the mitochondria to produce heat.

Inhibits: Purines
Activates: non-esterified FAs

46
Q

How are Brown Adipose Tissue formed in humans during chronic cold exposure?

A

Preadipocytes differentiate into Brown Adipose Tissue

47
Q

What 3 things can skeletal muscles use for energy?

A

FA, ketone bodies, glucose

48
Q

What is used as fuel for ATP synthesis in skeletal muscles in resting humans?

A
  • FAs from adipose

- Ketone bodies from liver

49
Q

What is used as fuel for ATP synthesis in skeletal muscles during moderate exercise?

A

Blood glucose, FA, Ketone bodies

50
Q

During moderate exercise, does the blood glucose undergo aerobic or anaerobic glycolysis?

A

Aerobic

51
Q

What is used as fuel for ATP synthesis in skeletal muscles humans undergoing vigorous exercise? Why?

A

Stored glycogen because of increased energy demand and reduced incoming oxygen

52
Q

What does the phosphocreatine buffering system provide? When does this conversion occur?

A

Phosphate group to make ATP –> during vigorous exercise.

53
Q

What happens in the phosphocreatine buffering system during recovery?

A

Phosphate group gets stored as phosphocreatine for future use.

54
Q

In muscle metabolism, each glucose from glycogen yeilds how many ATP? Why is this as the net normal yield is 2?

A

3

The end product of gluconeogenesis is G-1-P which is converted to G6P via phosphoglucomutase which doesn’t require ATP (simply transfers a phosphate)

55
Q

What does epinephrine help in muscle metabolism?

A

It helps using glucose from blood and glycogen

56
Q

What is a biproduct of vigorous exercise? What is the role of lactic acid?

A

Lactic acid which helps continue anaerobic glycolysis

57
Q

What is lactate converted to in the liver during recovery from activity?

A

Glucose

58
Q

What is another source of ATP during vigorous exercise?

A

Phosphocreatine –> creatine (produces ATP)

59
Q

What is happeing to muscles during shivering thermogenesis?

A

contracting vigorously, heat produced

60
Q

Does cardiac muscle (heart) undergo aerobic or anaerobic metabolism?

A

Aerobic!

61
Q

What organelle is present in abundance in cardiac muscle?

A

Mitochondria

62
Q

What is the main use of energy in cardiac muscles? What else can be used?

A

Mainly FAs, but ketone bodies and glucose can also be used

63
Q

What is energy production dependent on in cardiac muscles? Why?

A

Oxygen. Because main source of energy are FAs which undergo Beta-oxidation before becoming Acetyl-CoA & entering TCA cycle

64
Q

What are cardiac muscles sensitive to?

A

Cardiac deprivation

65
Q

What is cardiac muscle low in compared to liver and skeletal muscles?

A

Glycogen

66
Q

What are neurons highly dependent on for energy?

A

glucose

67
Q

The brain’s metabolism uses how many grams of glucose per day?

A

~130 g

68
Q

What can Brain Metabolism also use as a source of energy other than glucose? (during starvation)

A

Beta-hydroxybutyrate (ketone bodies)

69
Q

Why do neurons require LOTS of energy?

A

Because the ATP is mainly used to maintain the membrane potential (through Na-K-ATPase)

70
Q

What are astrocytes? What do they use as energy?

A

Non-neuronal brain cells that use FAs as energy

71
Q

How much stored glycogen can be found in the brain?

A

none!!!

72
Q

Is metabolism in brain an anaerobic or aerobic process?

A

Aerobic

73
Q

What are the two sources of energy during fasting/starvation? From which parts of the body?

A

Ketone bodies (from FA)

Glucose (from muscle protein)

74
Q

What enters the liver immediately after a calorie rich meal?

A

Glucose, fatty acids, & AAs

75
Q

Where is glucose exproted from here? What happens to the excess glucose in the liver?

A

Brain for energy needs

Adipose tissue

Muscle tissue

Excess glucose: oxidized to acetyl-CoA which is used to synthesize FAs for export as TAGs in VLDLs to adipose and muscle tissue.

76
Q

What happens to AAs that enter the liver?

A

Excreted as urea or used in protein synthesis for liver proteins.

77
Q

How do dietary fats move throughout the body? As what?

A

Lymphatic system from the intestine as chylomicrons –> to liver, muscle, & adipose tissues

78
Q

After several hours without a meal, what becomes the main source of glucose for the brain?

A

The liver via gluconeogenesis

79
Q

During fasting-state, what is used for gluconeogenesis in the liver?

A

AAs from degradation of proteins in liver, and glycerol from TAG breakdown in adipose tissue

80
Q

What is the liver’s main fuel during fasting-state?

A

FAs

81
Q

What is excess acetyl-CoA converted to in the liver during fasting-state?

A

Ketone bodies (for brain)

82
Q

While running a marathon, for what distance does your body provide you with free creatine and ATP?

A

80 meters

83
Q

While running a marathon, how long do your heart and lungs take to reach maximum capacity? Is anaerobic or aerobic glycolysis being used in this initial time period? How many ATPs produced?

A

2 minutes. Anaerobic glycolysis

2-3 ATP

84
Q

How long after one starts running a marathon do they begin to use aerobic respiration/glycolysis?

A

2 minutes (30-32 ATP)

85
Q

Is aerobic or anaerobic glycolysis used during uphill running? Why?

A

Anaerobic because heart and lungs are working as fast as they can

86
Q

After how long is runer’s high reached? Why?

A

45 minutes, endorphins peak

87
Q

How many grams of glycogen runs out after running 30k?

A

500 g

88
Q

What pathway has completely stopped functioning when runners hit the wall? What is all the energy created in the body being produced by?

A

Glycolysis

FA

89
Q

Why are FA not as efficient a source of ATP as Glucose?

A

Because FA oxidation is slow in ATP yield, making it harder to run

90
Q

Marathon runners use what type of muscles?

A

Slow twitch/dark

91
Q

Sprinters use what type of muscles?

A

Fast twitch/white

92
Q

During the first 40-60m of a 100m dash, where does the ATP come from?

A

phosphocreatine

93
Q

What AAs are used in the production of creatin from scratch?

A

Gly. Arg. Met.

94
Q

Is aerobic or anaerobic glycolysis occuring during the last 40 m of a 100 m dash? Is breaking required?

A

anaerobic. No, some runners take a deep breath then hold it!

Biochemistry 2 (8 decks)

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