Insulin

Question 1

The endocrine cells of the pancreas are arranged in clusters called the _______

Answer 1

islets of Langerhans

Question 2

Islets of Langerhans compose _% to _% of the pancreatic mass.

Answer 2

1

2

Question 3

There are approximately ______ islets of Langerhans, each containing about ____ cells.

Answer 3

1 million

2500

Question 4

The β cells compose __% of the islet and secrete ____.

Answer 4

65

insulin

Question 5

The α cells compose ___% of the islet and secrete ____.

Answer 5

20

glucagon

Question 6

The delta (δ) cells compose ___% of the islet and secrete ___.

The remaining cells secrete ______ or other peptides.

Answer 6

10

somatostatin

pancreatic polypeptide

Question 7

The central core of the islet of Langerhans contains mostly ___ cells, with α cells distributed ______.

The __ cells are interposed between α and β cells

Answer 7

β

around the outer rim

δ

Question 8

The islets receive about ___% of the total pancreatic blood flow.

Answer 8

10

Question 9

first hormone to be isolated from animal sources in a form that could be administered therapeutically to humans is _______

Answer 9

Insulin

Question 10

the first hormone to have its primary and tertiary structure determined is ______?

the first hormone to have its mechanism of action elucidated is _____ , while the first hormone to be measured by radioimmunoassay is _________?

the first hormone known to be synthesized from a larger precursor (prohormone); and the first hormone to be synthesized with recombinant DNA technology.

Answer 10

Insulin

Insulin

Insulin

Question 11

Pancreas is a Flattened organ

T/F

Answer 11

T

Question 12

Pancreas Lies ____peritoneally & (longitudinally or transversely?) across ____ abdominal wall

Answer 12

retro

transversely

posterior

Question 13

Pancreas is (anterior or Posterior?) to stomach, between duodenum on (left or right?) & spleen on (left or right?)

Answer 13

Posterior

Right

Left

Question 14

Pancreas is Classified as purely endocrine

T/F

Answer 14

F

endocrine & endocrine

Question 15

Somatostatin Inhibits secretion of insulin and stimulates secretion of glucagon

T/F

Answer 15

F

Inhibits insulin & glucagon

Question 16

Insulin is a peptide hormone consisting of two straight chains, an A chain (___ amino acids) and a B chain (__ amino acids).

Answer 16

21

30

Question 17

________ link the A chain to the B chain of insulin , and a ___________ is located within the A chain.

Answer 17

Two disulfide bridges

third disulfide bridge

Question 18

The synthesis of insulin is directed by a gene on ___, chromosome a member of a superfamily of genes that encode related growth factors.

Answer 18

11

Question 19

Stimulatory Factors of insulin secretion

___eased glucose concentration
___eased amino acid concentration
___eased fatty acid

Answer 19

Incr

Incr

Incr

Question 20

Decreased ketoacid concentration stimulates insulin secretion

T/F

Answer 20

F

Question 21

Hormones that stimulate insulin secretion are

______

_____

______

_____

Answer 21

glucagon

growth hormone

cortisol

GIP Potassium

Question 22

Vagal stimulation by _____

Answer 22

acetylcholine

Question 23

Sulfonylurea drugs e.g., ______ , _______ etc , (stimulate or inhibits) insulin secretion

Answer 23

tolbutamide

glyburide

Stimulates

Question 24

Obesity (stimulates or Inhibits ?) insulin secretion

Answer 24

Stimulates

Question 25

Inhibitory Factors of inulin secretion ____eased blood glucose ___ Adrenergic agonists

Answer 25

glucose α

Question 26

Fasting increases or inhibits insulin secretion

Answer 26

Inhibits

Question 27

Exercise stimulates or inhibits insulin secretion???

Answer 27

Inhibits

Question 28

Somatostatin stimulates or inhibits insulin secretion

Answer 28

Inhibits

Question 29

Diazoxide stimulates or inhibits insulin secretion

Answer 29

Inhibits

Question 30

Mechanisms of Insulin secretion by pancreatic cell Transport of ____ into the ___ cell Metabolism of ____ inside the cell occurs ATP closes ____ channel Depolarization cases ____ of calcium channels Increased ___cellular calcium causes insulin secretion

Answer 30

glucose; beta glucose ATP; potassium opening;calcium intra

Question 31

MECHANISM OF ACTION Insulin binds with the ____ subunit It elicits a change in the ___ subunit causing it to _______ ______ is activated causing further _____ of kinases and enzymes involved in insulin action Insulin receptor complex is then _____, meaning It is either ______ by ____, stored, or _____ to the cell membrane to be used again.

Answer 31

alpha beta; autophosphorylate Tyrosine kinase; phosphorylation internalized; degraded by proteases recycled

Question 32

Action of Insulin ``` ____eases glucose uptake into the cells ____eases glycogen formation ____eases glycogenolysis ___eases gluconeogenesis ____eases protein synthesis ____eases fat deposition _____eases lipolysis ____eases K + uptake into cells ```

Answer 32

Incr Incr Decr Decr Incr Incr Decr Incr

Question 33

Effect on Blood level ___ease blood glucose ____eases blood f.acid ____eases blood a.acid ____eases blood ketoacid _____eases blood [K+]

Answer 33

Decr Decr Decr Decr Decr

Question 34

Insulin-dependent diabetes mellitus or type __ diabetes mellitus , is caused by destruction of _____, often as a result of ______ process.

Answer 34

I β cells an autoimmune

Question 35

Inadequate Insulin secretion results in metabolic derangement of CHO, fat, and protein metabolism. T/F

Answer 35

T

Question 36

The nonreabsorbed glucose acts as an osmotic ____ in urine, producing an osmotic _____, poly___, and _____.

Answer 36

solute diuresis uria thirst

Question 37

Polyuria produces ECF volume (contraction or expansion?) and ___tension.

Answer 37

contraction hypo

Question 38

Lack of insulin also causes a shift of K + hyperkalemia (out or in?) of cells, resulting jn ____kalemia

Answer 38

Out Hyper

Question 39

Treatment of type I diabetes mellitus consists of ________ therapy.

Answer 39

insulin replacement

Question 40

Non insulin dependent diabetes mellitus ,or type __ diabetes MELLITUS, is often associated with ____.

Answer 40

2 obesity

Question 41

Type II diabetes mellitus is caused by _____ of _____ in target tissues and insulin _____.

Answer 41

down regulation insulin receptors resistance

Question 42

In type 2 diabetes, Insulin secreted cannot ______ on ____, ____, and _____; thus, insulin is unable to produce its usual metabolic effects.

Answer 42

activate its receptors muscle; liver ; adipose tissue

Question 43

Treatment of type II diabetes mellitus includes caloric ____ and weight ____ treatment with drugs e.g., _______ or ________, which _____ pancreatic insulin secretion; and treatment with ___ drugs (e.g., ____), which _____ insulin receptors on target tissues.

Answer 43

restriction reduction sulfonylurea tolbutamide or glyburide stimulate biguanide; metformin; upregulate

Question 44

GLUCAGON Secreted by the ____ cells.

Answer 44

alpha

Question 45

_______"mirror’s the image" of insulin

Answer 45

Glucagon

Question 46

insulin is the hormone of " ________"

Answer 46

abundance

Question 47

glucagon is the hormone of "_____."

Answer 47

starvation

Question 48

In contrast to insulin, which promotes storage of metabolic fuels, glucagon promotes their mobilization and utilization T/F

Answer 48

T

Question 49

Stimulatory factors for glucagon release Fasting T/F

Answer 49

T

Question 50

Decreased glucose concentration inhibits glucagon secretion T/F

Answer 50

F

Question 51

Increased amino acid concentration stimulates glucagon, especially ______ and ____)

Answer 51

arginine and alanine

Question 52

Cholecystokinin (CCK) inhibits glucagon T/F

Answer 52

F

Question 53

ACTIONS OF GLUCAGON ____eases glycogenolysis ____eases gluconeogenesis ____eases lipolysis ____eases ketoacid formation

Answer 53

Incr Incr Incr Incr

Question 54

Somatostatin Pancreatic somatostatin, a polypeptide with ____ amino acids, is secreted by the ___ Langerhans cells

Answer 54

14 δ

Question 55

Secretion of somatostatin is stimulated by the ingestion of all by 2 forms of nutrients T/F

Answer 55

F All forms

Question 56

Somatostatin secretion is inhibited by ____ via an ____ paracrine mechanism.

Answer 56

insulin intraislet

Question 57

Pancreatic somatostatin inhibits secretion of insulin and glucagon via ___ actions on the α and β cells.

Answer 57

paracrine

Question 58

GLUT2, a specific transporter for glucose that moves glucose from the ____ into the ___ by _____

Answer 58

blood cell facilitated diffusion

Question 59

_____________ (GIP)

Answer 59

glucosedependent insulinotropic peptide

Question 60

intravenous glucose is a more powerful stimulant for insulin secretion than oral glucose. T/F With reason

Answer 60

F The reason for this difference is that oral glucose stimulates the secretion of glucosedependent insulinotropic peptide (GIP), a gastrointestinal hormone that has an independent stimulatory effect on insulin secretion (adding to the direct effect of glucose on the β cells). Intravenous glucose does not cause the release of GIP and thus only acts directly

Question 61

Insulin increases glucose transport into target cells such as muscle and adipose by directing the insertion of glucose transporters (____) into the cell membranes

Answer 61

GLUT4

Question 62

Which glucose transporter takes glucose from blood, into the beta cell

Answer 62

GLUT 2