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MCAT Bio > Bio #5 > Flashcards

Bio #5 Flashcards

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1
Q

hypothalamus communicates with the anterior pituitary via the ________ and with the posterior pituitary via _____

A

hypophyseal portal system

nerves in the posterior stalk

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2
Q

hypothalamus releases

A

GnRH, GRH, TRH, GHRH, PIF

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3
Q

anterior pituitary releases

A

FSH/LH, ACTH, TSH, GH, Prolactin

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4
Q

posterior pituitary releases

A

oxytocin, ADH

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5
Q

what are the tyrosine derivitive hormones

A

catecholamines

T3, T4

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6
Q

what are the tyrosine derivative hormones

A

catecholamines (proteins)

T3, T4 (steroid)

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7
Q

_____ are the messengers of the endocrine system

A

hormones

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8
Q

glands

A

organs that secrete hormones

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9
Q

hormones

A

signaling molecules that are secreted directly into the bloodstream to distant target tissues. At target tissues they bind to receptors and either change gene expression or cellular functioning.

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10
Q

what are the different structures of hormones

A

peptide hormones
steroid hormones
amino acid derivative hormones

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11
Q

peptide hormones

A

made up of amino acids, ranging in size from quite small (such as anti-diuretic hormone, ADH) to relatively large (such as insulin)

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12
Q

naming of peptide hormones and steroid hormones

A

Most peptide and amino acid-derivative hormones end in “-in” or “-ine”. Most steroid hormones end in “-one”, “-ol” or “-oid”.

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13
Q

how are peptide hormones processed in the cell

A

 Many are cleaved during posttranslational modification and visit the Golgi to be modified before going to a certain place in the cell or being exocytosed.

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14
Q

how do peptide hormones function at their targets?

A

 Too large so they bind to extracellular receptor as first messenger and trigger transmission of second signal, second messenger.
 Signaling cascade: the connection between the hormone at the surface and the effect brought about by second messengers within the cell.
• Each step has the possibility of amplification.

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15
Q

signaling cascade

A

the connection between the hormone bound at the surface and the effect brought about by second messengers within the cell.
• Each step has the possibility of amplification.

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16
Q

peptide hormones are considered _____

A

first messengers

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17
Q

what are common second messengers

A
  • Cyclic adenosine monophosphate (cAMP)
  • Inositol triphosphate (IP3)
  • Calcium
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18
Q

explain the GPCR pathway

A

• Binding of peptide hormone either activates or inhibits enzyme adenylate cyclase, raising or lowering cAMP, cAMP can bind to intracellular targets such as protein kinase A, which phosphorylates txn factors like CREB which is the hormone’s ultimate affect. CREB changes gene expression in some way in the cell.

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19
Q

peptide hormones are ____ soluble which means they can _____ in the blood but they need to be _____ to get passed the cell membrane.

A

water
flow freely
exocytosed

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20
Q

peptide hormones have ______ effects

A

rapid but short lived

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21
Q

steroid hormones

A

derived from cholesterol and are produced primarily by the gonads and adrenal cortex.

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22
Q

what are peptide hormones and steroid hormones derived from

A

peptide: amino acids (or polypeptides)
steroid: cholesterol

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23
Q

steroid hormones ______ the cell membrane and bind to receptors in the ______

A

cross

cytoplasm or nucleus

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24
Q

steroid hormones have _______

A

slower, longer lives

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25
Q

describe steroid hormones in the bloodstream

A

they are non-polar, non-water soluble so they must be carried by proteins in the bloodstream
Ex: albumin: carries free fatty acids

hormones are generally inactive when bound

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26
Q

amino acids derivative hormones

A

(epinephrine, norepinephrine, triiodothyronine, and thyroxine) not as common but VERY important. Derived from one or two amino acids with a few modifications.
 Chemistry is wacky so it may be best to just memorize.
 Catecholamines (epinephrine and norepinephrine): bind to GPCR
 Thyroid hormone: binds intracellularly
 Thyroxine and triiodothyronine have slower onset but longer duration.

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27
Q

catecholamines

A

(epinephrine and norepinephrine): bind to GPCR

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28
Q

catecholamines are _____ hormones while thyroid hormones are ____ hormones

A

protein

steroid

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29
Q

direct hormones

A

secreted and then act directly on the target tissue

 Ex: insulin released by pancreas causes increased uptake of glucose by muscles.

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30
Q

tropic hormones

A

require an intermediary to act. Cause secretion of another hormone by a gland that then travels to the target tissue and acts.
 Ex: GnRH release from hypothalamus causes release of LH and FSH. LH and FSH activate other hormones which target tissues.

Have major effects on other endocrine tissues.

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31
Q

what are all of the endocrine glands

A

hypothalamus, pituitary, thyroid, parathyroid glands, adrenal glands, pancreas, the gonads (tests and ovaries), and the pineal gland

while the kidneys, gastrointestinal glands, heart, and thymus are involved.

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32
Q

hypothalamus

A

the bridge between the nervous and endocrine systems
o Regulated pituitary gland through tropic hormones. Very close to each other and connected via a portal system.
o Receives a lot of signals from everywhere.
o The release of hormones by the hypothalamus is regulated by negative feedback: occurs when a hormone (or product) later in the pathway inhibits hormones (or enzymes) earlier in the pathway.
 Saves energy and maintains homeostasis

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33
Q

interactions between the hypothalamus and pituitary gland

A

 Hypophyseal portal system: blood vessel system that directly connects the hypothalamus with the anterior pituitary (hypothalamus secretes compounds into it)
 The hormones from the hypothalamus bind to the receptors in the anterior pituitary and stimulate the release of other hormones.
 Hypothalamus release and anterior pituitary release:
• Gonadotropin-releasing hormone (GnRH)  follicle stimulating hormone (FHS) and luteinizing hormone (LH)
• Growth hormone-releasing hormone (GHRH)  growth hormone (GH)
• Thyroid-releasing hormone (TRH)  thyroid-stimulating hormone (TSH)
• Corticotropin releasing factor (CRF)  adrenocorticotropic hormone (ACTH)  release of cortisol by the adrenal cortex and then feedback loop (Example of an axes)
• Prolactin-inhibiting factor (PIF), dopamine  decrease in prolactin secretion (if no PIF is released then prolactin can be secreted)

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34
Q

hypophyseal portal system

A

only connects the hypothalamus to the anterior pituitary

blood vessel system that directly connects the hypothalamus with the anterior pituitary (hypothalamus secretes compounds into it)

 The hormones from the hypothalamus bind to the receptors in the anterior pituitary and stimulate the release of other hormones.

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35
Q

Hypothalamus release and anterior pituitary release:

A
  • Gonadotropin-releasing hormone (GnRH)  follicle stimulating hormone (FHS) and luteinizing hormone (LH)
  • Growth hormone-releasing hormone (GHRH)  growth hormone (GH)
  • Thyroid-releasing hormone (TRH)  thyroid-stimulating hormone (TSH)
  • Corticotropin releasing factor (CRF)  adrenocorticotropic hormone (ACTH)  release of cortisol by the adrenal cortex and then feedback loop (Example of an axes)
  • Prolactin-inhibiting factor (PIF), dopamine  decrease in prolactin secretion (if no PIF is released then prolactin can be secreted)
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36
Q

Posterior pituitary receives signals from the hypothalamus via _____

A

axons

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37
Q

hormones released by posterior pituitary

A

 Oxytocin: stimulates uterine contractions during labor. As well as milk letdown during lactation.
 Antidiuretic hormone: (ADH, vasopressin): increases reabsorption of water in the collecting ducts of the kidneys.
• Secreted in response to increased plasma osmolarity (increased concentration of solutes in the blood)

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38
Q

oxytocin

A

released by posterior pituitary, stimulates uterine contractions during labor. As well as milk letdown during lactation.

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39
Q

antidiuretic hormone

A

increases reabsorption of water in the collecting ducts of the kidneys.
• Secreted in response to increased plasma osmolarity (increased concentration of solutes in the blood)

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40
Q

what are the tropic hormones secreted by the anterior pituitary

A

FLAT
 FSH and LH act on gonads
 ACTH acts on the adrenal cortex
 TSH acts on the thyroid

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41
Q

what are the direct hormones secreted by the anterior pituitary

A

PEG
prolactin
endorphins
growth hormone

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42
Q

prolactin

A

more important in females, stimulates milk production in the mammary glands.
• High levels of estrogen and progesterone allow for the development of milk ducts in prep for lactation but milk does not come until prolactin and oxytocin (contraction of breast smooth muscle and ejection of milk through the nipple) are secreted.

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43
Q

endorphins

A

decrease the perception of pain

• Morphine mimics the effects of these.

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44
Q

growth hormone

A

promotes the growth of bone and muscle.
• Prevents glucose uptake in certain tissues that are not growing so that bone and muscle can have it. It also triggers the breakdown of fatty acids.
• Gigantism: excess of GH released during puberty
• Dwarfism: lack of GH released during puberty
• Acromegaly: gigantism in adults in which their smaller bones such as their hands or feet grow larger.

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45
Q

gigantism

A

excess of GH released during puberty

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46
Q

dwarfism

A

lack of GH released during puberty

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47
Q

acromegaly

A

gigantism in adults (after their epiphyseal plates close after puberty) in which their smaller bones such as their hands or feet grow larger.

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48
Q

posterior pituitary

A

Does not synthesize any hormones itself and the ones it releases are actually synthesized in the hypothalamus.

contains the nerve terminals of neurons with cell bodies in the hypothalamus
o ADH secreted in response to low blood volume or increased blood osmolarity
 Increases the permeability of the collecting duct to water from the filtrate in the nephron.  higher blood pressure and volume
o Oxytocin: secreted during childbirth and allows for coordinated contraction of uterine smooth muscle. Also promotes milk ejection through contraction of smooth muscle in the breast.
 May be involved in bonding behavior
 Is actually a positive feedback loop.

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49
Q

ADH/vasopressin

A

o ADH secreted in response to low blood volume or increased blood osmolarity
 Increases the permeability of the collecting duct to water from the filtrate in the nephron.  higher blood pressure and volume

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50
Q

oxytocin

A

secreted during childbirth and allows for coordinated contraction of uterine smooth muscle. Also promotes milk ejection through contraction of smooth muscle in the breast.
 May be involved in bonding behavior
 Is actually a positive feedback loop.

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51
Q

thyroid

A

o Controlled by the thyroid-stimulating hormone (TSH) from the anterior pituitary
o Located on the front side of the trachea
o Two functions
 1. Sets basal metabolic rate: releases triiodothyronine (T3) and thyroxine (T4)
 2. Promotes calcium homeostasis through the release of calcitonin

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52
Q

Triiodothyronine (T3) and Thyroxine (T4) are _____ hormones

A

thyroid hormones
steroid
amino acid derivative hormones

 Both produced by the iodination of the amino acid tyrosine in the follicular cells of the thyroid.
• 3 and 4 refer to the number of iodine atoms attached to tyrosine.
 Can make energy production more or less efficient and alter the utilization of glucose and fatty acids.
 Increased triiodothyronine (T3) and thyroxine (T4) lead to increased cellular respiration.

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53
Q

T3 and T4 hormones are very important for ____

A

energy regulation

alter utilization of glucose and fatty acids increase them leads to increased cellular respiration

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54
Q

hyperthyroidism

A

excess thyroid hormone, tumor or overstimulation

Heightened activity level, increased respiratory and heart rate (pretty much the opposite of hypothyroidism)

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55
Q

calcitonin

A

released from the thyroid gland
 Decreases plasma calcium levels in 3 ways: increase excretion in kidneys, decrease calcium absorption in the gut, increase storage of calcium in the bone.

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56
Q

calcitonin does what to plasma calcium levels

A

decreases it

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57
Q

what is calcium important for

A
  • bone structure and strength
  • release of neurotransmitters from neurons
  • regulation of muscle contraction
  • clotting of blood (calcium is a cofactor)
  • also plays a role on cell movement and exocytosis of cellular materials.
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58
Q

GnRH

A

gonadotropin releasing hormone

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59
Q

FSH

A

follicle stimulating hormone

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60
Q

LH

A

luteinizing hormone

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61
Q

GHRH

A

growth hormone releasing hormone (GNRH)

62
Q

GH

A

growth hormone

63
Q

FLAT PEG

A

FLAT: tropic
PEG: direct

64
Q

TRH

A

thyroid releasing hormone

65
Q

TSH

A

thyroid stimulating hormone

66
Q

CRF

A

corticotropin releasing factor

67
Q

ACTH

A

adrenocorticotropic hormone ACTH

68
Q

PIF

A

prolactin inhibiting factor

69
Q

prolactin

A

mother prepares to lactate

70
Q

parathyroid glands

A

o Four pea-sized structures that sit on the posterior surface of the thyroid.
o Parathyroid hormone (PTH) released from them.
o Antagonistic to calcitonin and raises blood calcium levels
 Opposites of calcitonin
 Negative feedback
o Also plays a role in phosphorous homeostasis, getting rid of it, and also absorbing it.
o Activates vitamin D: required for absorption of calcium and phosphate from the gut.

71
Q

parathyroid hormone

A

released from them.
o Antagonistic to calcitonin and raises blood calcium levels
 Opposites of calcitonin
 Negative feedback

72
Q

what activates vitamin D

A

PTH: Activates vitamin D: required for absorption of calcium and phosphate from the gut.

73
Q

adrenal gland

A

are located on top of the kidneys. Each adrenal gland has a cortex and a medulla.

74
Q

adrenal cortex

A

secretes corticosteroids, can be divided into 3 classes:

salt-sugar-sex

75
Q

glucocorticoids

A

adrenal cortex
steroid hormones that regulated glucose levels and affect protein metabolism
o Cortisol: released in times of stress
o Cortisone and cortisol raise blood glucose by increasing gluconeogenesis and decreasing protein synthesis. Can also decrease inflammation and immunological responses.
o CRF from hypothalamus  ACTH from anterior pituitary  glucocorticoids

76
Q

mineralocorticoids

A

adrenal cortex
used in salt and water homeostasis, with their most profound affects on the kidneys.
o Aldosterone: increases sodium reabsorption in the distal convoluted tubule and collecting duct of the nephron. Water follows the sodium ions into the bloodstream which increases blood volume and pressure.
 No change in osmolarity
 Decreases reabsorption of potassium and hydrogen ions in the same segments of the nephron.
 Under control of angiotensin-aldosterone system: decreased blood pressure causes the juxtaglomerular cells of the kidney to secrete renin, which cleaves an inactive plasma protein, angiotensinogen, to its active form angiotensin I. Angiotensin I is then converted to angiotensin II by angiotensin-converting enzyme (ACE) in the lungs. Angiotensin II stimulates the adrenal cortex to secrete aldosterone.

77
Q

cortical sex hormones

A

adrenal cortex

78
Q

cortisol

A

released in times of stress.

along with cortisone, increases blood glucose level

79
Q

angiotensin-aldosterone system (explain and draw)

A

decreased blood pressure causes the juxtaglomerular cells of the kidney to secrete renin, which cleaves an inactive plasma protein, angiotensinogen, to its active form angiotensin I. Angiotensin I is then converted to angiotensin II by angiotensin-converting enzyme (ACE) in the lungs. Angiotensin II stimulates the adrenal cortex to secrete aldosterone.

80
Q

hypothyroidism

A

 Hypothyroidism: a deficiency of iodine or inflammation of the thyroid  thyroid hormones are secreted in insufficient amounts or not at all.
• Lethargy, slow heart rate and respiratory rate
• Cretinism: intellectual and developmental delay caused by thyroid deficiency.

81
Q

cortical sex hormones

A

androgens and estrogens
o Play a larger role in females because the male tests already secrete large amounts of hormones.
o Excess cortical hormones can lead to genotypic male or female having phenotypic problems

82
Q

adrenal medula

A

o Nestled inside the adrenal cortex
o Derivative of the Nervous system
o Produces epinephrine and norepinephrine. Both are part of larger class called catecholamines.
 Can be secreted directly into the blood stream.
o System wide effects all centered on the fight or flight response.
 Increase breakdown of glycogen to glucose in liver and muscle and increase metabolic rate.
 Dilate bronchi, increase heart rate.
 Fast stress response
 Vasodilation of blood vessels and shunts blood flow to systems used in the sympathetic response.

83
Q

epinephrine and norepinephrine

A

 Increase breakdown of glycogen to glucose in liver and muscle and increase metabolic rate.
 Dilate bronchi, increase heart rate.
 Fast stress response
 Vasodilation of blood vessels and shunts blood flow to systems used in the sympathetic response.

84
Q

pancreas

A

o Has both endocrine and exocrine (secrete substances directly into ducts) functions

endocrine: islets of langerhans cells secrete hormones into blood vessels.
exocrine: acinar cells secrete digestive enzymes into the pancreatic duct

alpha cells: glucagon
beta cells: insulin
delta cells: somatostatin

85
Q

exocrine function

A

secrete substances directly into a duct

86
Q

acinar cells

A

pancreas

secrete digestive enzymes into the pancreatic duct

87
Q

islets of langerhans cells

A

secrete hormones into blood vessels.

small clusters of hormone-producing cells grouped together in the pancreas
• Islets contain 3 distinct types of cells: alpha (glucagon), beta (insulin), and delta (somatostatin) cells

88
Q

glucagon

A

secreting during times of fasting, when glucose levels are low. Triggers glycogenolysis, gluconeogenesis, and degradation of protein and fat

89
Q

insulin

A

antagonistic to glucagon and secreted when blood glucose levels are high. Induces muscle and liver cells to take up glucose and store it as glycogen for later. Triggers fat and protein synthesis.

90
Q

hypoglycemia

A

when insulin is in excess, low blood glucose concentration

91
Q

hyperglycemia

A

: excess glucose in the blood, when insulin is underproduced or not secreted or insensitivity to insulin.

92
Q

diabetes mellitus type I vs. type II

A

 Hyperglycemia: excess glucose in the blood, when insulin is underproduced or not secreted or insensitivity to insulin.
• Can result in diabetes mellitus.
o Type I: insulin-dependent, autoimmune destruction of the beta cells of the pancreas resulting in little or no insulin production.
o Type II: non-insulin dependent, receptor-level resistance to the effects of insulin.

93
Q

polyuria

A

increased frequency of urination

94
Q

polydipsia

A

increased thirst

95
Q

somatostatin

A

an inhibitor of both insulin and glucagon secretion. High blood glucose and amino acid concentrations, also released by hypothalamus to decrease growth hormone secretion.

96
Q

gonads

A

o Testes: secretes testosterone in response to gonadotropins (LH and FSH)
 Testosterone causes sexual differentiation of the male during gestation and promotes development and maintenance of secondary sex characteristics in males.
o Ovaries: secrete estrogen and progesterone in response to gonadotropins (LH and FSH)
 Estrogen is involved in the development of the female reproductive system during gestation and also promotes development and maintenance of secondary sex characteristics in females.
 Estrogen and progesterone also govern the menstrual cycle

97
Q

testes

A

secretes testosterone in response to gonadotropins (LH and FSH)
 Testosterone causes sexual differentiation of the male during gestation and promotes development and maintenance of secondary sex characteristics in males.

98
Q

ovaries

A

secrete estrogen and progesterone in response to gonadotropins (LH and FSH)
 Estrogen is involved in the development of the female reproductive system during gestation and also promotes development and maintenance of secondary sex characteristics in females.
 Estrogen and progesterone also govern the menstrual cycle

99
Q

pineal gland

A

o Located deep within the brain and secretes melatonin.
 Melatonin is involved in circadian rhythms.
 Receives projections from the retina, responds to decreases in light intensity possibly.

100
Q

melatonin

A

 Melatonin is involved in circadian rhythms.

 Receives projections from the retina, responds to decreases in light intensity possibly.

101
Q

gastrointestinal tract endocrine secretions

A

secretin, gastrin, and cholecystokinin

102
Q

kidneys endocrine secretions

A

o Kidneys produce erythropoietin which stimulates bone marrow to increase erythrocyte production (red blood cells) when low blood oxygen levels are sensed.

103
Q

heart endocrine secretions

A

o The heart releases atrial natriuretic peptide (ANP) to help regulate salt and water balance.
 Functionally antagonistic to aldosterone.

104
Q

thymus endocrine secretions

A

o The thymus releases thymosin which is important for proper T-cell development and differentiation.

105
Q

Type I diabetes vs. Type 2 diabetes

A

Type I: no insulin is produced
Type 2: insensitivity to insulin

blood glucose levels rise to dangerous levels.

106
Q

what do hormones change when they reach their receptor?

A

cellular functioning or gene expression

107
Q

amplification during the peptide hormone signaling cascade

A

each step can result in an increase in signal intensity.

108
Q

What are some examples of second messengers in the peptide hormone pathway?

A

cyclic adenosine monophosphate (cAMP), inositol triphosphate (IP3) and calcium

109
Q

albumin

A

nonspecific protein that binds to steroid hormones and transports them in blood

110
Q

steroid hormones are _____ when bound to their carrier protein

A

inactive

111
Q

what receptors do catecholamines use?

what receptors do thyroid hormones use?

A

GPCR (making them more like peptide hormones)

intracellular (making them more like steroid hormones)

112
Q

the thyroid hormones regulate _____

A

metabolic rate

113
Q

where are some of the locations the hypothalamus receives input from?

A

light input from the retinae to control sleep-wake cycles, increases in blood osmolarity, regulates appetite and satiety.

114
Q

what is another name for the pituitary gland?

A

the hypophysis

115
Q

what is another name for prolactin inhibiting factor?

A

dopamine

116
Q

three organ systems are referred to as ____

A

axes

117
Q

all of the final products of the hypothalamus endocrine system have _____ effects on the hypothalamus and the anterior pituitary

A

negative feedback

118
Q

milk production in makes is always ____

A

pathogenic

119
Q

oxytocin vs. prolactin

A

oxytocin is released from the posterior pituitary and is responsible for milk let down during lactation
prolactin is released from the anterior pituitary and is responsible for milk production during lactation

120
Q

where does bone growth originate?

A

epiphyseal plates

121
Q

the posterior pituitary does not actually produce oxytocin or ADH, it just _______ them after they are produced by the hypothalamus

A

stores

122
Q

which hormone has a positive feedback loop?

A

oxytocin has a positive feedback loop with uterine contractions. Uterine contractions promote more oxytocin release which promotes greater uterine contractions.

123
Q

what occurs if blood concentration is too high or if blood volume is low?

A

triggers ADH release from the hypothalamus/posterior pituitary

124
Q

how are T3 and T4 produced?

A

via the iodination of the amino acid tyrosine in the follicular cells of the thyroid

125
Q

what is the disease cretinism caused by?

A

a deficiency in T3 and T4 during childhood. Characterized by disability and developmental decay.

126
Q

in the thyroid, ____ cells produce thyroid hormones and ____ cells produce calcitonin

A

follicular cells

C-cells (or parafollicular cells)

127
Q

calcitonin ____ calcium levels in the blood

A

decreases

calciton-INTO bones, excretion from kidneys, decreased absorption from gut.

128
Q

what are the important roles of calcium?

A

bone structure and strength
release of neurotransmitters from neurons
regulation of muscle contraction
clotting of blood (calcium is a cofactor)
calcium is also involved in cell movement and exocytosis

129
Q

what does bone resorption entail?

A

brings bone back into blood (parathyroid hormone)

130
Q

parathyroid hormone activates vitamin _____ which is required for the absorption of _______ and _____ in the gut

A

calcium and phosphate

131
Q

plasma phosphate ____ plasma Ca+2

A

decreases

132
Q

many people who suffer from joint pain are treated with _______ injections into the joint space to decrease ____

A

glucocorticoids

inflammation

133
Q

aldosterone

A

released from the adrenal cortex
type of mineralcorticoid
plays a role in salt and water homeostasis. Reabsorbs salt and water from the collecting duct and the distal convoluted tubule of the nephron.

134
Q

what are ACE inhibitors?

A

block the conversion of angiotensin I to angiotensin II which inhibits vasoconstriction and allows the heart to not work as hard (treatment of high blood pressure and congestive heart failure).

135
Q

what are the functions of the corticosteroids?

A

adrenal cortex
salt (mineralcorticoids)
sugar (glucocorticoids)
sex (cortical sex hormones)

136
Q

cortisol is for _____ stress responses while catecholamines are for ____ stress responses

A

long term

fast

137
Q

the pancreas has both ___ and ___ functions

A

endocrine and exocrine

138
Q

exocrine means

A

into digestive tract/for that purpose

139
Q

the hormone producing cells of the pancreas are grouped together into _____ which contain what types of cells

A

islets of Langerhans

alpha, beta, and delta cells

140
Q

alpha cells of the pancreas produce ____

A

glucagon

141
Q

beta cells of the pancreas produce ___

A

insulin

142
Q

delta cells of the pancreas produce ____

A

somatostatin

143
Q

what is often reported by diabetics?

A

polyuria and polydipsia.

144
Q

what are counterregulatory hormones?

A

raise blood glucose levels: growth hormone, glucocorticoids, epinephrine, glucagon.

145
Q

oxytocin and antidiuretic hormone are ____ hormones

A

peptide

146
Q

ANP is a ____ hormone

A

peptide

147
Q

reabsorption of something from the kidneys means ______

A

it is taken out of the kidneys (not excreted) but reabsorbed into the blood stream

148
Q

gallactorhea

A

is a milky nipple discharge unrelated to the normal milk production of breast-feeding.

caused by prolactin overabundance

149
Q

all of the hormones released from the adrenal cortex are _____ hormones

A

steroid

150
Q

somatostatin release is triggered by ______

A

high blood glucose or amino acids or certain gastrointestinal hormones.

151
Q

for hormones, the suffix “in” indicates ______

A

peptide hormone or amino acid derived hormone

MCAT Bio (12 decks)

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