Quiz 1 Flashcards

1
Q

where in the body does gluconeogenesis occur?

A

liver, kidneys, small intestine

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

which tissues exhibit high PPP activity?

A

lactating mammary glands
phagocytic cells
lung and liver tissue

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

Normal alpha linoleic acid (ALA) intake percentage in adults?

0.6-1.2%
5-10%
10-35% 
20-35% 
45-65%
A

0.6-1.2%

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

describe how insulin and glucagon influence glycolysis

A

glucagon inhibits

insulin increases

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

what is the rate limiting step of glycolysis and what are its players?

A

fructose-6-phosphate (phosphofructokinase) fructose-1,6-bisphosphate)

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

what are the essential fatty acids?

A

linolenic acid
alpha linolenic acid

conditionally DHA and EPA

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

describe how glucose influences glycolysis

A

excess inhibits

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

which three steps in glycolysis are irreversible and what are the players in each?

A

glucose (hexokinase/glucokinase) glucose-6-phosphate
fructose-6-phosphate (phosphofructokinase) fructose-1,6-bisphosphate
phosphoenolpyruvate (pyruvate kinase) pyruvate

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

disease characterized by loss of pancreatic beta cell function. what is the result of this dysfunction

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

diabetes;

insulin deficiency, resistance

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

where is glycogen stored?

A

liver and muscle

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

Normal fat intake percentage in adults?

0.6-1.2%
5-10% 
10-35% 
20-35% 
45-65%
A

20-35%

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

which is the rate limiting step of gluconeogenesis and what are the players of this reaction?

A

F-1,6-BP (F16BPhosphatase) F-6-P

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

Which fatty acids can be found in the outer leaflet of the cell membrane?

A

Sphingomyelin
Glycolipids
Phosphatidylcholine

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

What fatty acids can be found in the inner leaflet of the cell membrane?

A

Phosphotidylinositol
Phosphotidylserine
Phosphotidylethanolamine

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

Ca2+ concentration is greater inside the cell or outside the cell?

A

Outside

10000 fold!!

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

K+ concentration is greater inside the cell or outside?

A

Inside

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

Na+ concentration is greater inside or outside the cell?

A

Outside

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

Cl- concentration is greater inside or outside the cell?

A

Outside

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

What is the difference between P-type ATPases and ABC transporters?

A

With P type ATPases, the protein is phosphorylated

The protein is not phosphorylated in ABC transporters

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

After ATP hydrolysis, where does phosphorylation occur on P-type ATPases?

A

On an aspartate residue

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

After ATP hydrolysis, where does phosphorylation occur on ABC transporters?

A

ABC transporters are not phosphorylated

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

The sodium potassium pump is an example of which type of transporter?

A

P-type ATPase

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

Antibiotic resistance is a result of upregulation of which type of transporter?

A

ABC transporters

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

The sodium-glucose transporter is an example of which type of transport?

A

Secondary active
Symporter
Gradient maintained by the sodium potassium pump

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

The sodium calcium exchanger is what type of transporter?

A

Secondary active
Anti porter
Gradient maintained by the sodium potassium pump

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

Describe the function of the sodium-calcium exchanger (NCX)

A

3Na+ down concentration gradient

1 Ca+ against concentration gradient

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

Describe how D-glucose and D-galactose are transported from the intestinal lumen into the bloodstream

A

Secondary active transport into the enterocyte via SGLT1 transporter
Facilitated diffusion into blood stream via GLUT2

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

Describe how fructose is transported from the intestinal lumen into the bloodstream

A

Facilitated diffusion into enterocyte via GLUT5 on apical side
Facilitated diffusion into bloodstream via GLUT2 on basal side

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

What maintains sodium concentration gradient and resides on the basal side of the enterocyte membrane in the small intestine?

A

Na+/K+ pump

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

A salad has 8g of protein, 10g of carbs and 20g of fat with the dressing. To drink, you have a beer that contains 30g of carbs and 5g of alcohol. How many calories is this meal?

A
Protein = 4 cals/g
Carbs = 4cals/g
Fats = 10cals/g
Alcohol = 7cals/g

427cals

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

how would you determine how much protein an individual needed?

A

nitrogen from urine sample

1g nitrogen = 6.25 g protein

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

where is GLUT7 located and what is its significance?

A

in the ER

part of G6Phosphatase (G6P—>glucose)

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

this type of glycogen provides a fuel reservoir for physical activity

A

muscle glycogen

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

glycogen is reduced and extended from which end?

reducing end
non reducing end

A

non reducing

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

where in glycolysis is ATP produced for the first time and what are the players in this reaction?

A

1,3-bisphosphoglycerate (phosphoglycerate kinase) 3-phosphoglycerate

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

where in the body does glycolysis occur?

A

exercising muscle, RBCs, brain

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

describe how ATP and AMP influence glycolysis

A

ATP inhibits

AMP increases

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

what is the net yield of glycolysis?

A

2 ATP
2 Pyruvate
2 NADH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

hypoglycemia and a buildup of lactate are hallmark traits of which disorder affecting the rate limiting gluconeogenesis? similar Tarui disease

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

F-1,6-BPhosphatase deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

which disease would most directly impact the rate limiting step of glycolysis? why?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

Tarui disease; PFK-1 deficiency

41
Q

what effect does glucagon have on PFK-2/FBPase-2? why?

A

phosphorylates via protein kinase A; because the enzyme assumes phosphatase function, dephosphorlating F2,6BP to fom F6P which can be used for gluconeogenesis

42
Q

what is the rate limiting step of the pentose phosphate pathway and what are the players in this reaction?

A

G6P (G6PD) lactone

43
Q

function of glycogen in muscle?

A

fuel reservoir for physical activity

44
Q

fasting hypoglycemia, lactic acidosis, and glycogen buildup from the inability to convert G6P to glucose is characteristic of which disease?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

Von Gierke disease (GSD1a)

45
Q

Normal carbohydrate intake percentage in adults?

0.6-1.2%
5-10%
10-35% 
20-35% 
45-65%
A

45-65%

46
Q

disease characterized by elevated lactate dehydrogenase and unconjugated bilirubin. what does this elevation say?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

hemolytic anemia;

those are normally intracellular components that must mean cell lysis

47
Q

disease caused by mutation in GLUT2 transporter? where is this transporter located and what affinity does it have for glucose?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

fanconi-bickel

48
Q

what effect does glucagon have on PK? why?

A

phosphorylates PK via protein kinase A; phosphoenol pyruvate can enter gluconeogenesis

49
Q

fructose is taken up in the liver via which GLUT transporter?

1
2
3
4
5
6
7
A

5

50
Q

when is glycolysis favored?

A

when blood glucose/insulin is high

51
Q

_______ fats are most linked to increased risk of cardiovascular disease

saturated
unsaturated
trans
cis

A

trans

52
Q

how does gluconeogenesis “bypass” the key regulatory steps of glycolysis? which enzymes are bypassed by which?

A

pyruvate carboxylase and PEP carboxykinase (pyruvate kinase)
F-1,6-BPhosphatase (PFK)
G-6-Phosphatase (hexokinase/glucookinase)

53
Q

describe the function and significance of the Cori cycle

A

lactate from anaerobic glycolysis in RBC and exercising muscle is used in the liver to regenerate glucose that is transported back to those muscles for energy
prevents lactate accumulation

54
Q

which end of glycogen possesses glycogenin?

reducing end
non reducing end

A

reducing end

55
Q

what effect does insulin have on PFK-2/FBPase-2? why?

A

dephosphorylates via protein phosphatases; because the enzyme assumes kinase activity, phosphorylating F6P to F2,6BP which activates PFK-1 and drives the rate limiting step of glycolysis

56
Q

this type of glycogen regulates blood glucose levels

A

liver glycogen

57
Q

Overweight range for BMI?

A

25-29.9

58
Q

Normal range for BMI?

A

18.5-24.9

59
Q

what are the functional roles that fiber has on glycemic index? and how much is recommended daily?

A

helps to reduce glycemic load
aides in gut absorption and motility

20-35g/day
~14g/1000kcal

60
Q

diabetes would most heavily impact the function of which GLUT transporter and why? this transporter is present in which types of tissues?

1
2
3
4
5
6
7
A

4
these transporters are insulin dependent
skeletal muscle, adipose, heart

61
Q

which are negative regulators of glycolysis?

F-6-P
F-1,6-P
F-2,6-P
Glucose
G-6-P
citrate
AMP
insulin
glucagon
cortisol
ATP
A
F-6-P
citrate
G-6-P
glucagon
cortisol
ATP
62
Q

t/f

insulin signaling causes the fusion of vesicles with the plasma membrane and placement/insertion of the GLUT1 transporter?

A

f

only GLUT4 transporters are insulin dependent

63
Q

what is the “trapping” step of glycolysis and what are its players?

A

glucose (hexokinase/glucokinase) glucose-1-phosphate

64
Q

which are positive regulators of glycolysis?

F-6-P
F-1,6-P
F-2,6-P
Glucose
G-6-P
citrate
AMP
insulin
glucagon
cortisol
ATP
A
F-1,6-P
F-2,6-P
Glucose
insulin
AMP
65
Q

what effect does insulin have on PK? why?

A

dephosphorylates P via protein phosphatases; to stimulate glycolysis (phosphoenol pyruvate—->pyruvate)

66
Q

which step of gluconeogenesis is the only one that occurs in the mitochondria and what are the players of this reaction?

A

pyruvate (pyruvate carboxylase) OAA

67
Q

this disease is characterized by a deficiency in PFK-1, exercise induced muscle weakness, and hemolytic anemia

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

Tarui disease

68
Q

which is the reversible phase of the pentose phosphate pathway?

oxidative
non oxidative

A

non oxidative

69
Q

Normal linoleic acid intake percentage in adults?

0.6-1.2%
5-10%
10-35% 
20-35% 
45-65%
A

5-10

70
Q

function of glycogen in liver?

A

blood glucose regulation

71
Q

where in glycolysis is NADH produced and what are the players in this reaction?

A

glyceraldehyde-3-phosphate (GAPDH) 1,3-bisphosphoglycerate

72
Q

Normal protein intake percentage in adults?

0.6-1.2%
5-10% 
10-35% 
20-35% 
45-65%
A

10-35%

73
Q

where in glycolysis is ATP produced for the second and final time and what are the players in this reaction?

A

phosphoenolpyruvate (pyruvate kinase) pyruvate

74
Q

PFK-2/FBPase-2 is a bifunctional enzyme that acts as a kinase in its _______ form and as a phosphatase in its ______ form

A

dephosphorylated

phosphorylated

75
Q

describe the differences between hexokinase and glucokinase in terms of location, affinity, and regulation

A

hexokinase is present in all cells, has high affinity for glucose, and is inhibited by G6P

glucokinase is only present in the liver and pancreas, has low affinity for glucose and is regulated by insulin and glucagon

76
Q

where does gluconeogenesis take place within the cell?

A

starts in the mitochondria, completes in the cytosol

77
Q

describe where each of the GLUT transporters are found (1-4)

A

1) ubiquitous
2) liver/pancreas
3) neurons
4) skeletal muscle, adipose, heart

78
Q

which GLUT transporter has the lowest affinity for glucose?

A

GLUT2

79
Q

where in carbohydrate metabolism is biotin used as a cofactor and what are this reactions players?

A

pyruvate (pyruvate carboxylase) oxaloacetate

80
Q

which is usually caused by some sort of deficiency in PK?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

hemolytic anemia

81
Q

patient presents with failure to thrive, and accumulation of galactitol, which disease would be representative of this presentation?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

galactosemia

82
Q

deficiency in glucose 1P uridyltransferase (GALT) leads to this disease. what is a consequence of this disease?

diabetes
hemolytic anemia
fanconi-bickel syndrome
Von Gierke disease (GSD1a)
galactosemia
Tarui
A

galactosemia

accumulation of galactitol

83
Q

what is the precursor for fatty acid synthesis?
where in the cell is it formed?
where in the cell is it actually used for FA synthesis and how does it get there?

A

acetyl CoA
mitochondria
cytosol
links up with OAA to form citrate, shuttled across the mito membranes to the cytosol, converted back to acetyl CoA and OAA

84
Q

what is the rate limiting step of FA synthesis and what are the players in this reaction?

A

acetyl CoA (acetyl CoA carboxylase) malonyl CoA

85
Q

where in FA synthesis is biotin used as a cofactor and what are the players in this reaction?

A

acetyl CoA (acetyl CoA carboxylase) malonyl CoA

86
Q

what is the substrate for FA synthase? what other role does it serve?

A

malonyl CoA

inhibits carnitine acyltransferase (rate limiting step in FA degradation)

87
Q

describe the order of reactions catalyzed by FA synthase

A

condensation
reduction
dehydration
reduction

CRDR

88
Q

describe describe the allosteric regulators of FA synthesis (acetyl CoA carboxylase)

A

citrate promotes

palmitate/long chain FAs inhibit

89
Q

describe the effects of each of these regulators of FA synthesis (acetyl CoA carboxylase)

insulin
glucagon
epinephrine
AMP

A

insulin: dephosphorylates via protein phosphatases; activates
glucagon/epinephrine: phosphorylates via PKA; inactivates
AMP: inactivates via AMP kinase

90
Q

which molecule serves as a carbon donor in FA elongation in the SER?

A

malonyl CoA

91
Q

which molecule serves as a carbon donor in FA elongation in the mitochondria?

A

acetyl CoA

92
Q

describe TAG synthesis in intestinal cells.

What molecules are produced and where are they released?

A

TAGs from diet broken down to MAGs and FFAs > DAGs > TAGs > chylomicrons release into lymphatics and enter blood via thoracic duct

93
Q

describe TAG synthesis in hepatocytes.

what molecules are produced and where are they released?

A

glucose/glycerol > G3P + fatty acyl CoA (x2) > DAGs > TAGs > VLDLs released into the blood

94
Q

TAG synthesis in the intestines is promoted by _______

A

dietary TAGs

95
Q

TAG synthesis in hepatocytes is promoted by _______

A

excess carbohydrates

96
Q

describe TAG synthesis in adipocytes.

what molecules are produced and where are they released?

A

dietary glucose > G3P + fatty acyl CoAs (from chylomicrons and VLDLs) > DAGs > TAGs stored in adipocytes themselves

97
Q

what is the rate limiting step of FA degradation and what are the players in this reaction?

A

fatty acyl CoA (carnitine palmitoyltransferase I) fatty acyl carnitine

98
Q

describe the order of reactions in beta oxidation

A

oxidation
hydration
oxidation
thiolysis