Brainscape's Knowledge GenomeTM

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


See full index

Physio - E2 - Lecture Slides > L-6 Energy Balance and Metabolism I > Flashcards

L-6 Energy Balance and Metabolism I Flashcards

1
Q

describe the energy production

A
  • oxidation; make ATP

1) proteins
2) Carbs
3) fats

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

describe the energy utilization

A

consume ATP

  • active ion transport
  • muscle contraction
  • synthesis of molecules
  • cell division and growth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

describe the delta G

A
  • std free energy difference
    = difference in free energy when 1 mole of each reactant is converted to 1 mole of each product at 1 atm pressure at 25 degrees C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what becomes the final common pathway for the transport of almost all the carbs to the tissue cells?

A

glucose

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

T/F: galactose, glucose, and fructose are all interconvertible

A

true

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

what two hexoses can be converted to fructose-6-phosphate to enter the glycolytic pathway?

A

galactose and glucose

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

describe the two type of glucose uptake

A

via active sodium-glucose co-transport and facilitated transport

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

where does sodium-glucose co-transport occur? describe it

A

GI tract and renal tubules

- active transport of sodium provides energy for absorbing glucose against a concentration gradient

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

where does facilitated transport occur? describe it

A

most tissues

  • only transported from higher to lower concentration
  • presence of insulin increases glucose transport x10
  • phosphorylation of glucose prevents diffusion out of cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

in what tissues can the phosphorylation be reversed?

A
  • phosphorylation can be reversed in liver, renal, and intestinal cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what 3 important enzymes are involved in glycogenesis and glycogenolysis? what do they do?

A
  • glucokinase - transfers phosphate from ATP
  • phosphatase (removes phosphate)
  • phosphorylase (catalyzes production of glucose-1-phosphate from glycogen)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what factors can activate phosphorylase?

A
  • epinephrine (from adrenal medulla)

- glucagon (from alpha cells of pancreas)

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

what are the effects of phosphorylase?

A
  • promotes conversion of glycogen to glucose

- glucose can then be released into blood

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

in glycolysis, what are the end products?

A
  • 2 pyruvic acid
  • 4 hydrogens (released via dehydrogenase)
  • 2 ATP (net)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the end products of converting pyruvate to acetyl-CoA?

A
  • 2 Acetyl-CoA
  • 4 Hydrogen
  • 2 CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

describe the citric acid cycle and its end products

A
  • occurs in the mitochondrial matrix
  • 16 H’s
  • 2 ATPs
  • 4 CO2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is the net reaction of the citric acid cycle?

A

2 Acetyl-CoA + 6H20 + 2ADP –> 4 CO2 + 16 H + 2 CoA + 2 ATP

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

where does oxidative phosphorylation occur?

A

mitochondrial cristae

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

what is the fate of hydrogen atoms from previous cycles?

A
  • note that hydrogens are removed in pairs
  • one member of each pair becomes a H ion
  • the other member combines with NAD+ –> NADH
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the fate of electrons removed from H ions?

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

what are the major components of the ETC?

A
  • flavoprotein
  • several ion sulfide proteins
  • Ubiquinone (Q)
  • cytochrome A3 (cytochrome oxidase) // located on inner membrane; can give up two electrons to oxygen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

number of ATPs formed per glucose molecule:

A
  • glycolysis: 2 ATP
  • CAC: 2 ATP
  • oxidative phosphorylation: 34 ATP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the max number of ATPs per glucose molecule?

A

38 ATP

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

what is the efficiency?

A

66%

456,000/686,000 = 66%

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

what is the pentose phosphate pathway?

A

the ppp is a cyclical pahtway in which one molecule of glucose is metabolized for each revolution of the cycle

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

describe some details about it

A
  • for every 6 molecules of glucose that enter the pathway, 5 molecules of glucose are resynthesized
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is this pathway used for?

A

mostly used for the synthesis of fats and other substances

-

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

Where are the hydrogens generated from this pathway bound to?

A

NADP+ instead of NAD+

29
Q

what can be used for the synthesis of fats from carbohydrates? NADP or NAD?

A

NADP+ (as NADPH)

30
Q

how is glucose broken down when theres an excess of glucose in liver?

A

PPP; producing excess NADPH

31
Q

what does this NADPH participate in?

A
  • in the conversion of Acetyl-CoA into fatty acid chains
  • glucose is preferentially stored as glycogen until the storage cells (liver and muscle) are saturated
  • excess glucose is then converted into fat (liver and fat cells) and stored in fat cells
32
Q

describe what happens when triglyceride absorption occurs from intestinal lumen

A
  • most triglycerides are digested into monoglycerides and fatty acids
  • intestinal epithelial cells resynthesize these into triglycerides that enter the lymph as chylomicrons
  • apoprotein B is adsorbed to the chylomicron surfaces
33
Q

how are chylomicrons transported to the venous system?

A

via the thoracic ducts

34
Q

what tissues are chylomicrons especially removed from (from their blood)?

A
  • adipose tissue
  • skeletal muscle
  • heart
35
Q

what do these last three tissues synthesize?

A
  • lipoprotein lipase, which:
    = is transported to surface of capillary epithelial cells
    = hydrolyzes chylomicron triglycerides, releasing fatty acids and glycerol
36
Q

some more fun facts about neutral fats

A
  • fatty acids can be used for fuel or again synthesized into triglycerides
  • 50% of the plasma fatty acid is replaced every 2-3 minutres
  • therefore, all normal energy requirements of the body can be provided by the oxidation of fatty acids without using carbs or proteins as an energy source
37
Q

under what conditions is there an increase in utilization of fat for energy?

A
  • starvation

- diabetes mellitus

38
Q

what type of lipoprotein is synthesized by intestinal cells/

A

chylomicrons

39
Q

what kinda lipoproteins are synthesized by the liver?

A
  • very low density lipoproteins (VLDLs)
  • intermediate DLs
  • low DLs
  • High DLs
40
Q

describe the lipid transport in the blood via VLDLs

A
  • high concentration of triglycerides and moderate amounts of cholesterol and phospholipids
  • transport lipids mainly from liver to adipose tissue
41
Q

LDLs

A
  • high concentration of cholesterol and moderate concentration of phopsholipids
42
Q

HDLs

A
  • high concentration of proteins and low concentration of cholesterol and fatty acids
43
Q

what are the principal functions of the liver in lipid metabolism?

A

text***

44
Q

under what conditions do large quantities of triglycerides appear in the liver?

A

text***

45
Q

what are triglycerides hydrolyzed into? (in regards to energy source)

A
  • into fatty acids and glycerol, which are transported in blood to tissue
46
Q

what two type of cells dont use fatty acids for energy?

A

brain cells and RBCs

47
Q

what is glycerol converted to?

A

G3P

48
Q

what are fatty acids converted to? and where?

A

Acetyl-CoA; in mito

49
Q

via what process? elaborate

A

via beta-oxidation

  • carnitine is used as a carrier molecule into the mitochondria
  • Acetyle CoA enters the citric acid cycle by binding to oxaloacetic acid
  • hydrogens enter the chemoismotic oxidative system
50
Q

what are the products from beta-oxidation of one molecule of stearic acid?

A
  • 9 ACA molecules

- 146 molecules of ATP

51
Q

what happens to fatty acids in liver not used for metabolism?

A

releases many ACAs

  • 2 ACAs condense to form acetoacetic acid
  • some of the acetoacetic acid is converted to: b-hydroxybutyric acid and acetone
52
Q

T/F: acetoacetic acid is a keto acid

A

True

53
Q

what are considered ketone bodies?

A
  • acetoacetic acid
  • beta-hydroxybutyric acid,
  • acetone
54
Q

what happens to ketone bodies during ketosis?

A
  • diffuse back into cells and are converted into ACA
55
Q

how does ketosis occur/

A

if concentration of ketone bodies increase above normal in blood

56
Q

what conditions favor ketosis?

A
  • starvation
  • diabetes
  • diet composed almost entirely of fat
57
Q

how many steps are involved in synthesis of fatty acids? what do they involve?

A

2;

  • involves malonyl-CoA
  • NADPH
58
Q

why is fat synthesis important?

A
  • more fat can be stored in tissues than carbs

- weight-for-weight, fat contains about 2.5x the energy of carbs

59
Q

why are fats poorly synthesized during insulin insufficiency?

A

text

60
Q

why are carbs preferred over fats for energy?

A

text

61
Q

describe the development of atherosclerotic plaque

A
  • damage to vascular endothelium
  • circulating monocytes and LDLs accumulate at injury site
  • monocytes
62
Q

describe damage to vascular endothelium

A
  • incr the expression of adhesion molecules

- decreases release of NO and other substances that prevent adhesion of macromolecules and cells

63
Q

describe monocytes

A
  • cross endothelium
  • enter intima
  • become macrophages
64
Q

describe macrophages

A
  • ingest lipoproteins
  • become foam cells
  • form visible fatty streaks
65
Q

describe fatty streaks

A
  • grow larger

- coalesce

66
Q

surrounding fibrous and smooth muscle tissues

A
  • proliferate

- form large plaques

67
Q

descirbe the large plaques

A
  • may occlude lumen
  • may become sclerotic or fibrotic
  • may become calcified
68
Q

what are the basic causes of atherosclerosis?

A
  • increased LDLs

- familial hypercholesterolemia (defective LDL receptors)

69
Q

note about HDLs

A

they may be able to absorb cholesterol crystals that are beginning to be deposited in arterial walls

Physio - E2 - Lecture Slides (8 decks)

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