Brainscape's Knowledge GenomeTM

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


See full index

Endocrine (updated 2016) > 12 Pancreas > Flashcards

12 Pancreas Flashcards

1
Q

Where is insulin produced

A

β-cells of pancreas

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

What is the precursor to the active form of insulin

A

proinsulin

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

What are the two chains of insulin

A

Alpha chain and beta chain linked by disulfide bonds

C-peptide is cut out of the proinsulin molecule but also secreted

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

Is insulin similar across species

A

Yes; highly conserved

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

What fragment of the proinsulin molecule is used to monitor endogenous insulin secretion post-injection

A

C-peptide fragment

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

Why is the C molecule useful

A

released in equimolar amounts with insulin
Is a ‘record’ of endogenous secretion
Is a way of measuring endogenous insulin levels

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

What are the actions of insulin?

A

Glucose metabolism

1) facilitates glucose uptake by most tissues
- exceptions: RBCs, most of the brain, intestinal mucosa, lens of the eye, kidney tubules
2) facilitates glucose storage as glycogen
3) lowers blood glucose
4) fat metabolism
5) protein metabolism
6) mineral metabolism

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

What does insulin do to blood glucose levels? How?

A

lowers blood glucose by:

  • transports glucose into cells by carrier-mediated facilitated diffusion
  • converts glucose to glycogen in liver
  • converts glucose to TGs in adipose
  • inhibits gluconeogenesis in liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is glucose converted into in the liver

A

glycogen

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

What is glucose converted to in adipose tissue

A

Triglycerides

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

What does insulin do to the liver

A

inhibits gluconeogenesis

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

What does insulin do to fat metabolisim

A

inhibits hormone-sensitive lipase (decreases lipolysis)
Promote fat deposition
Triglyceride synthesis

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

What does insulin do to protein metabolism

A

Increase AA transport into cells
Increase protein synthesis
Synergizes with GH

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

What does insulin do to mineral metabolism

A

transports K+ into cells

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

Is insulin anabolic or catabolic

A

anabolic (builds things up)

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

How is glucose metabolism maintained when blood glucose is high (hyperglycemia)

A

Increase glucose > increase insulin secretion > glucose cellular uptake (in muscle, fat)

decrease endogenous production of glucose > increased utilization of glucose (muscle & adipose cells) AND increased storage of glucose (in liver a glycogen), fat and aa arriving in the blood from GI tract

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

What are three major consequences of Insulin deprivation on CHO metabolisim

A

Glycosuria
Polyuria
Polydypsia

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

What are some consequences of insulin deprivation on fatty acid metabolism

A

lipolysis stimulated > formation of acetoacetic acid > formation of ketone bodies >
Ketoaciduria
Ketoacidosis: fruity breath > COMA > DEATH

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

What 3 conditions release insulin

A

High glucose
High AA
High FFA

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

What inhibits insulin

A

epinephrine

21
Q

Where is glucagon produced

A

α-cells of pancreas

22
Q

Is glucagon similar across species

A

yes; highly conserved in various species

23
Q

What does glucagon do in the liver?

5 things

A

Increase gluconeogeneis
- increases every rate limiting enzyme
Increase glycogenolysis
- if glycogen is present it is mobilized
Decreases glyconeogenesis

Increase protein catabolism
Increase lipolysis

24
Q

What does glucagon do in the liver

A

overall Increases glucose output

25
Q

What stimulates glucagon secretion?

A 
Decreased glucose
Elevated AA (also stimulates insulin)
26
Q

What inhibits glucagon secretion?

A

High free fatty acids (FFA)

27
Q

What does glucagon do to muscle

A

Increase FFA

indirectly inhibits glucose uptake by muscle and fat

28
Q

What does glucagon do to adipose tissue

A

Promotes lypolisis

29
Q

What is a normal blood glucose level 4mM

A

between 70-110mg/dl (90 is the mean)

below 70 = hypoglycemia
above 180 = hyperglycemia

30
Q

What does somatostatin do to insulin and glucagon

A

inhibits release

31
Q

What stimulates somatostatin

A

increased AA

glucose

32
Q

What is the overall effect of somatostatin

A

Decrease glucose

decreased glucose transport across gut wall
- decreased gut blood flow

33
Q

What hormone is hypoglycemic

A

insulin (only one)

34
Q

α- cells of the pancreas make

A

glucagon (mobilizes glucose)

35
Q

β-cells of the pancreas make

A

insulin (stores glucose)

36
Q

δ-cells of the pancreas make

A

somatostatin (regulatory, inhibits endocrine pancreas)

37
Q

What hormones are hypoglycemic?

A

ONLY insulin

there is no plan-B

38
Q

gluconeogenesis

A

the synthesis of glucose from noncarbohydrate sources, such as amino acids and glycerol. It occurs primarily in the liver and kidneys whenever the supply of carbohydrates is insufficient to meet the body’s energy needs.

stimulated by cortisol and other glucocorticoids and by the thyroid hormone thyroxine.

39
Q

What are the major actions of insulin

A

↑ glucose transport into muscle & adipose cells
↓ blood glucose

↑ intracellular metabolic use of glucose
↑ glycogen synthesis in liver and muscle cells
↓ gluconeogenesis (in the liver)

↑ intracellular transport of aa & lipids and protein & triglyceride synthesis
↑ overall body growth (general effect)

40
Q

How does insulin deprivation affect CHO metabolism?

A

insulin deficiency blocks glucose uptake & increases liver glycogenolysis > increase in serum glucose > increased glucose filtration in kidneys > glucose overload in kidneys

this causes:
glycosuria, polyuria, and polydypsia

41
Q

define glycosuria (glucosuria)

A

glucose in the urine

when you loose glucose in the urine it drags water with it

42
Q

polyuria

A

excessive urination

43
Q

polydypsia

A

excessive thirst

44
Q

Is glucagon anabolic or catabolic in terms of glycogen metabolism?

A

catabolic

it is used in situations where there is no fuel coming in but continued need for energy

45
Q

If the body is hyperglycemic (high blood glucose) how does it normalize?

A

β-cells of pancreas release insulin
liver takes up glucose and stores it as glycogen
body / fat cells take in glucose from the blood
normal blood glucose levels are acheived

46
Q

If the body is hypoglycemic (low blood glucose) how does it normalize?

A

α-cells of the pancreas release glucagon
liver breaks down glycogen and releases glucose into the blood
normal blood glucose levels are achieved

47
Q

Where is somatostatin produced?

A

δ-cells of pancreas
GI tract
hypothalamus

(multiple forms 14 or 28 aa)

48
Q

What happens to your blood sugar after you eat 10 chocolate chip cookies for lunch? How long does it take for insulin to be secreted?

A

blood sugar increases
insulin quickly released
- stored in pancreas and ready for release

49
Q

You are on an 8-hr hike and you miss lunch. Does your blood sugar crash as you expend energy all day? What hormone would be increased in this metabolic situation?

A

no

glucagon

Endocrine (updated 2016) (19 decks)

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