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Flashcards in Endocrine System Deck (103):
0

Glands that secrete products into body cavities, the lumen of organs, or to the outer surface of the body are called what?

Exocrine glands

1

Glands the secrete products into the interstitial fluid, most of which diffuse into the blood and are carried throughout the body are called what?

Endocrine glands

2

Name the five endocrine glands of the body.

Pituitary, thyroid, parathyroid, adrenal, and pineal glands

3

Name the thirteen organs and tissues that, in addition to their other functions, also secrete hormones.
SPLIT KOSH PATH

Skin, pancreas, liver, intestine (small), thymus, kidneys, ovaries, stomach, hypothalamus, placenta, adipose tissue, testes, and heart

4

A decrease in the number of target-cell receptors for a hormone is called what?

Down-regulation

5

An increase in the number of target-cell receptors is called what?

Up-regulation

6

Hormones that act on the cell that secreted them are called what?

Autocrines

7

Hormones that act on neighbouring cells to the one from which they are secreted, but that do not diffuse into the blood are called what?

Paracrines

8

Autocrines and paracrines, together are known as what?

Local hormones

9

Hormones that diffuse into the blood and travel throughout the body are known as what?

Circulating hormones

10

What are the three types of fat-soluble hormones?

Steroid hormones, thyroid hormones, and nitric oxide (NO)

11

What are the three kinds of water-soluble hormones?

Amine hormones, peptide hormones, and eicosanoid hormones

12

In order to travel through the blood, lipid-soluble hormones often attach to what?

Transport proteins

13

What gland secretes melatonin?

Pineal gland

14

Name the seven hormones secreted by the anterior pituitary gland.
HGH, TSH, ACTH, FSH, LH, MSH, and ...

Human growth hormone, thyroid stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone, melanocyte-stimulating hormone, and prolactin

15

All releasing and inhibiting hormones are secreted by what organ?

Hypothalamus

16

When a water-soluble hormone binds to a receptor on its target cell membrane, it becomes known as what?

First messenger

17

The first messenger activates the production of a second messenger inside the cell. One common second messenger is cyclic AMP (cAMP).
In the process, what does adenylate cyclase convert into cAMP?

ATP

18

What does cAMP stand for?

Cyclic adenosine monophosphate

19

What are the three factors that determine the responsiveness of a target cell to a hormone?

Concentration of hormone in the blood, number of receptors on the target cell, and the influence of other hormones

20

When one hormone requires recent or simultaneous exposure to another hormone in order to carry out their function, this is known as what?

Permissive effect

21

When two different hormones acting together increase the effect of either hormone acting alone, this is known as what?

Synergistic effect

22

When one hormone opposes the action of another hormone, this is known as what?

Antagonistic effect

23

What three types of signals control hormone secretion?

Signals from nervous system, chemical changes in blood, and the actions of other hormones

24

What connects the hypothalamus to the pituitary gland?

Infundibulum

25

The adenohypophysis is another name for what gland?

Anterior pituitary

26

Neurohypophysis is another name for what?

Posterior pituitary

27

The anterior pituitary is composed of epithelial tissue and the posterior pituitary is composed of what?

Nervous tissue

28

What system transports hormones from the hypothalamus to the pituitary gland?

Hypophyseal portal system

29

What is the name of the cells in the hypothalamus that produce the releasing and inhibiting hormones?

Neurosecretory cells

30

The pituitary gland rests in a cavity of what bone?

Shpenoid

31

Anterior pituitary hormones that act on other endocrine glands are called what?

Tropic hormones

32

What cells secrete human growth hormone?

Somatotrophs

33

What cells secrete thyroid-stimulating hormone?

Thyrotrophs

34

What cells secrete the gonadotropins FSH and LH?

Gonadotrophs

35

What cells secrete prolactin?

Lactotrophs

36

What cells secrete adrenocorticotropic hormone?

Corticotrophs

37

Melanocyte-stimulating hormones are secreted by what cells?

Corticotrophs

38

What are the five releasing hormones secreted by the hypothalamus?

GHRH, TRH, GnRH, PRH, and CRH

39

What are the two inhibiting hormones released by the hypothalamus?

GHIH and PIH

40

Human growth hormone promotes the synthesis and secretion of what small protein hormone?

Insulin-like growth factor

41

What are found within the hypothalamohypophyseal tract?

Axons of the neurosecretory cells of the hypothalamus

42

What are the four functions carried out by insulin-like growth factors?

Increases uptake of amino acids,
decreases breakdown of proteins,
enhances lipolysis in adipose tissue,
and decreases glucose uptake into cells

43

What do PRL, PRH, PIH, and CRH stand for?

Prolactin, prolactin-releasing hormone, prolactin-inhibiting hormone (dopamine), and corticotropin-releasing hormone

44

Abnormally low blood glucose concentration is a condition known as what?

Hypoglycemia

45

Abnormally high blood glucose concentration is known as what?

Hyperglycemia

46

Hypoglycemia stimulates the hypothalamus to secrete what hormone?

GHRH

47

Hyperglycemia stimulates the hypothalamus to secrete what hormone?

GHIH

48

In addition to the secretion of HGRH by the hypothalamus, identify three more stimuli that promote the secretion of HGH by somatotrophs in the anterior pituitary gland.

Decreased fatty acids with increased amino acids in the blood,
deep sleep (stages 3 & 4),
increase activity of the sympathetic nervous system (exercise),
other hormones such as glucagon, estrogen, cortisol, and insulin

49

What are the three zones of the adrenal cortex, from outer to inner?

Zona glomerulosa, zona fasciculata, and zona reticularis

50

Mineralocorticoids, such as aldosterone, are secreted by what layer of the adrenal cortex?

Zona glomerulosa

51

What three things does the follicle-stimulating hormone stimulate?

Development of ovarian follicles,
secretion of estrogen,
production of sperm

52

What hormone triggers ovulation?

Luteinizing hormone (LH)

53

After estrogens, progesterone, glucocorticoids, human growth hormone, thyroxine, and insulin exert their permissive effects, what hormone is then effective in stimulating mammary glands to produce milk?

Prolactin (PRL)

54

What hormone is also known as dopamine?

Prolactin-inhibiting hormone (PIH)

55

Hyper secretion of prolactin causes what?

Galactorrhea (inappropriate lactation) and amenorrhea (absence of menstrual cycles)

56

What two hormones does the posterior pituitary store and release?

Oxytocin and antidiuretic hormone (ADH)

57

Antidiuretic hormone is also known as what?

Vasopressin

58

What vessel supplies blood to the posterior pituitary?

Inferior hypophyseal arteries, which branch from the internal carotid arteries

59

What two main things does oxytocin stimulate?

Uterean contractions (with stretching of the cervix) and milk ejection (with suckling stimulus)

60

What five related effects does antidiuretic hormone (ADH) have on the kidneys?

Increase in water reabsorption, decrease in urine production, decreased sweating, smooth muscle constriction of arteriole walls, all of which contribute to increased blood pressure

61

What cells in the hypothalamus monitor blood osmotic pressure?

Osmoreceptors

62

What cells in the thyroid gland secrete T3 and T4?

Follicular cells

63

What are the other names for T4 and T3?

Thyroxine (or tetraiodothyronine) and triiodothyronine

64

What do the parafollicular cells of the thyroid gland produce?

Calcitonin

65

What large glycoprotein do the follicular cells of the thyroid produce in addition its hormones?

Thyroglobulin (TGB)

66

What is the amino acid on the thyroglobulin protein to which iodine molecules attach when in the lumen of thyroid follicles?

Tyrosine

67

What is the transport protein that binds to T3 and T4 when these hormones enter the bloodstream?

Thyroxine-binding globulin (TBG)

68

What are some of the actions of thyroid hormones?

Increases metabolic rate
Stimulates synthesis of sodium-potassium pumps
Increases body temperature
Stimulates protein synthesis
Increases the use of glucose and fatty acids for ATP production
Stimulates lypolysis
Regulates growth of nervous and bone tissue
Enhances some actions of epinephrine and norepinephrine

69

How does calcitonin decrease blood calcium levels?

By inhibiting osteoclasts from breaking down the extracellular matrix of bone

70

When calcium levels in the blood are low, what three ways does parathyroid hormone act to bring the calcium levels back up?

By increasing the number and activity of osteoclasts,
by slowing the loss of calcium to the urine,
and by stimulating the kidneys to release calcitriol which increases absorption of calcium from the gastrointestinal tract

71

The zona fasciculata secretes glucocorticoids; what is the primary glucocorticoid it secretes?

Cortisol

72

The deepest layer of the adrenal cortex, the zona reticularis, secretes what hormones?

Androgens

73

What are three stimuli that will initiate the renin-angiotensin-aldosterone (RAA) pathway?

Dehydration, sodium deficiency, and hemorrhage

74

Decreased blood pressure stimulates juxtaglomerular cells of the kidneys to secrete renin, which converts angiotensinogen into angiotensin I.
Primarily in what organ does angiotensin-converting enzyme (ACE) convert angiotensin I into angiotensin II?

Lungs

75

Angiotensin II stimulates the zona glomerulosa of the adrenal cortex to secrete aldosterone;
What two things does aldosterone do in the kidneys?

Increases reabsorption of sodium into the blood, thus causing increased water reabsorption,
and increases secretion of potassium and hydrogen ions into the urine

76

The most abundant glucocorticoid (95%) is cortisol; what are two others?

Corticosterone and cortisone

77

What are six effects of glucocorticoids?

Increased protein breakdown
Gluconeogenesis
Lipolysis
Stress resistance
Anti-inflammatory effects
Depressed immune response

78

Dehydroepiandrosterone (DHEA) is formed in the zona reticularis of the adrenal cortex. In adult females, what are its functions?

Promotes libido and are converted into estrogens, the sole source after menopause

79

What tissue type makes up the adrenal medulla?

Nervous tissue

80

What are the cells of the adrenal medulla that produce and release epinephrine (80%) and norepinephrine(20%)?

Chromaffin cells

81

What are the other names of epinephrine and norepinephrine?

Adrenaline and noradrenaline

82

What is the essential function of the hormones epinephrine and norepinephrine?

Intensifies/augments sympathetic (fight-or-flight) nervous system response

83

99% of pancreatic cells are exocrine, and called what?

Acini

84

What is another name for the endocrine pancreatic islets?

Islets of Langerhans

85

What are the four types of hormone secreting cells found in the pancreatic islets, and what do each produce?

Alpha cells (17%of islet cells): glucagon
Beta cells (70%): insulin
Delta cells (7%): somatostatin (aka GHIH)
F cells (6%): pancreatic polypeptide

86

Glucagon stimulates glycogenolysis and what?

Gluconeogenesis

87

Insulin stimulates the uptake of glucose into cells and what two other processes?

Glycogenesis and lipogenesis

88

Somatostatin (GHIH) inhibits the secretion of growth hormone and what else?

Glucagon & insulin

89

Insulin release is also stimulated by acetylcholine released by the parasympathetic vagus nerve fibres that innervate the pancreatic islets, by the amino acids arginine and leucine, and by what hormone?
GIP

Glucose-dependent insulinotropic peptide (GIP)

90

Glucagon release is also stimulated by what?

Exercise (increased sympathetic nervous system activity) and high amino acid concentration in the blood, as after a high-protein meal

91

What are four hormones secreted by ovaries?

Estrogens (estradiol and estrone), progesterone, inhibin, and relaxin.

92

What hormone is related to the muscle atrophy that occurs with aging?

Human growth hormone

93

Hyposecretion of human growth hormone during the growth years slows bone growth and closes epiphyseal plates before normal height is reached. This condition is called what?

Pituitary dwarfism

94

Hypersecretion of human growth hormone during childhood causes what condition?

Giantism

95

Hyperscretion of human growth hormone during adulthood is known as what condition?

Acromegaly

96

Diabetes insipidus results from faulty receptors (nephrogenic DI) or lack of secretion (neurogenic DI) of what hormone?

Antidiuretic hormone (ADH)

97

The most common form of hyperthyroidism is what condition?

Graves' disease, an autoimmune disorder in which the person produces antibodies that mimic the action of thyroid-stimulating hormone (TSH)

98

Graves' disease patients often develop edema behind the eyes, which is called what?

Exophthalmos, which causes the eyes to protrude

99

An enlarged thyroid gland is called what?

Goiter

100

Hypersecretion of the glucocorticoid cortisol by the adrenal cortex produces what?

Cushing's syndrome, with symptoms of spindly arms and legs, "moon face", a "buffalo hump" on the back, and a hanging abdomen

101

Hyposecretion of glucocorticoids and aldosterone is what condition?

Addison's disease,

102

What is the most common endocrine disorder?

Diabetes mellitus, caused by an inability to produce or use insulin