Chapter 16 endocrine Flashcards

1
Q

Compare and contrast the nervous system and endocrine system

A

endocrine: controls body functions using chemical signals (hormones)
nervous sys: controls body functions using electrical signals (action potential)

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2
Q

what tissue are endocrine glands made of?

A

epithelial tissue

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3
Q

where do endocrine glands excrete hormones to?

A

blood stream

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4
Q

why are endocrine glands highly vascularized?

A

to be able to release hormone into blood supply

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5
Q

what are unicellular endocrine glands vs multicellular?

A

uni: a single cell is the entire gland
multi: the gland is composed of more than just a single cell

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6
Q

what are examples of unicellular endocrine glands?

A

i cells releasing CCK
m cells releasing motilin
g cells releasing gastrin

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7
Q

what is another name for multicellular endocrine glands?

A

ductless glands

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8
Q

what is the signaling cell?

A

“talker cell” makes and releases chemical signal

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9
Q

what is the signaling molecule?

A

“voice - small chemical that travels between cells

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10
Q

what is the target cell?

A

“listener cell” - cell that recognizes the sent chemical signal

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11
Q

what is a receptor?

A

“ears” protein on or inside target cells that binds to signaling molecule

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12
Q

what are autocrine chemical signals? example?

A

used by cell to signal to itself
immune cells in compliment cascade

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13
Q

what kind of cell signal across gap junctions?

A

cardiac muscle cells/ pacemaker cells

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14
Q

what are paracrine chemical signals? example?

A

signal between two different cells in the same approx location
ex: juxtaglomerular macula densa cells releasing NO and ATP to cause vasodilation/constriction

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15
Q

what are endocrine chemical signals? example?

A

signal is released into the blood to regulate other cells farther away
ex: glucagon, insulin

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16
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A
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17
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18
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19
Q

Describe the difference between amino acid based and steroid based hormones

A

amino acid: mostly water-soluble (polar)/ receptor on outside of cell/ responses are rapid and short term
steroid: lipid soluble/ receptor located inside of cell/ actions are slow and long term

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20
Q

why are thyroid hormones a special exception?

A

they are amino-acid based but are nonpolar (like steroid)

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21
Q

where would the TH receptor be located?

A

inside the cell

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22
Q

where do amino-acid based hormones bind to receptors?

A

on outside of cell

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23
Q

where do steroid-based hormones bind to receptors on cell?

A

inside the cell

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24
Q

because steroid based hormones cause slow, long-term changes, what period of life would they be abundant?

A

puberty

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25
Q
A
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26
Q

do lipid soluble hormones need signal transduction cascades?

A

no, they have the receptors on inside of cell, so no need

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27
Q

Compare and contrast the mechanism of water-soluble vs lipid soluble hormones

A

water-soluble: need second messengers for signal transduction
lipid- soluble: do not need second messenger

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28
Q

what are the possible effects of hormones on target cells?

A

change membrane potential
cause production of new enzymes/proteins
activate/deactivate enzymes
cause secretion
stimulate cellular reproduction

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29
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A
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30
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31
Q
A
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32
Q

mechanism regulating hormone release in humoral? example?

A

changes in blood characteristics cause hormone release

glucose levels go up, insulin is released to allow cellular glucose uptake
glucose levels are too far down, glucagon is released to increase blood glucose levels

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33
Q

mechanism regulating hormone release in neural? example?

A

input from neurons cause hormone release
ex: epinephrine is released in response to activation of SNS

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34
Q

mechanism regulating hormone release in hormonal? example?

A

initial hormone causes the release of a second hormone
ex: “releasing hormones” from hypothalamus -> pituitary -> other endocrine glands

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35
Q
A

leptin is controlled by hormonal stimuli

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36
Q

Describe how hormone levels, number of receptors, and affinity affect the degree of target cell activation

A

hormone levels: higher hormone concentration will have strongest response “shouting”

number of receptors: cells with more receptors will have a stronger response “has more ears”

affinity: high affinity receptor will cause stronger response because they bind easily to more hormones

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37
Q

Describe ways two or more hormones can combine their effects on a target cell
o Permissiveness
o Synergism
o Antagonism

A

o Permissiveness - one hormone is required before another to fully activate cells
o Synergism - effect on target cell is stronger if two hormones are present
o Antagonism - one hormone opposes the action of another (insulin/glucagon)

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38
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A
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39
Q
A
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40
Q

where is the pituitary situated in?

A

in the hypophyseal fossa of the sphenoid bone

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41
Q

what is the posterior pituitary made of?

A

neurohypophysis (made of nervous tissue)

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42
Q

what is the anterior pituitary gland made of?

A

adenohypophysis (made of glandular epithelial tissue)

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43
Q

what is the region that connects pituitary to hypothalamus called?

A

infundibulum

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44
Q

is the pituitary gland the “boss” of the endocrine system?

A

no, the hypothalamus is the actual boss, but we used to believe the pituitary gland was

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45
Q

where does the infundibulum of the pituitary gland connect to?

A

the hypothalamus

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46
Q

Compare and contrast how the neurohypophysis and adenohypophysis are connected to the hypothalamus

A

anterior: is connected via the hypophyseal portal system (several types of blood vessels)
posterior: neurons start in hypothalamus and end in pituitary gland where they can release their hormones (neuroendocrine cells)

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47
Q

where is oxytocin synthesized?
where does it go?

A

synthesized by paraventricular nucleus in hypothalamus -> posterior pituitary -> uterus/ breast tissue/ brain

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48
Q

what effect does oxytocin have once it has been delivered to uterus/ breast tissue/ brain?

A

uterus: stim smooth muscle to cause birth
breast: stim smooth muscle to cause milk ejection
brain: feeds back to brain as a neurotransmitter to increase sexual and affectionate behavior

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49
Q

what triggers the release of oxytocin? what kind of stimuli are each?

A

hormonal stimuli: increased estrogen (like in late pregnancy)

neural stimuli: mechanical stimulation (suckling) of breast tissue
stretching of uterus
sight, smell, sound of baby

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50
Q

what is the synthetic drug to replace oxytocin? what is its use?

A

Pitocin - speeds up labor

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51
Q

what decreases/slows oxytocin?

A

stress reduces

alcohol and THC slows responses

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52
Q

where is ADH (antidiuretic hormone) made and released?

A

supraoptic nucleus of hypothalamus -> posterior pituitary -> kidneys (V2 receptors)/ arteries (V1 receptors)

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53
Q

what do the V2 receptors in the kidneys cause to happen when ADH binds to them?

A

causes aquaporin insertion in collecting duct in order to promote water reabsorption, increase blood volume, and decrease urine output

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54
Q

What do the V1 receptors in the arteries cause to happen when ADH binds to them?

A

causes vasoconstriction to increase blood pressure

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55
Q
A
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56
Q
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57
Q

knowing what ADH does, when would it need to be released?

A
  • high blood osmolarity = dehydration
  • low blood volume
  • nicotine (bad side effect causes vasodilation b/c it increases ADH release)
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58
Q

what does a lack of ADH release cause? what can cause this?

A

diabetes insipidus - causes dilute urine because ADH no longer promotes water reabsorption
can be caused by head trauma damaging supraoptic nucleus in hypothalamus

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59
Q
A
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60
Q
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61
Q
A

the neurons go straight to posterior pituitary from the hypothalamus
these neurons are what directly carry the signal

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62
Q

what cell type in the anterior pituitary releases growth hormone?

A

somatotropic cells

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63
Q

what does GH stimulate?

A

tissue building (physical anabolic growth)
triggers release of energy stores that power growth (metabolic)

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64
Q

what tells somatotropic cells to release GH? what tells them to inhibits GH?

A

GHRH (growth hormone releasing hormone) released by hypothalamus

Somatostatin (GHIH) released by hypothalamus inhibits release

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65
Q

what effects does direct effects of GH cause?

A

increases blood sugar
increases metabolism of fats

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66
Q

what effects does indirect effects of GH cause? what does indirect mean?

A

indirect means that GH goes to liver and activated IGFs (insulin-like growth factors) to then go and tell skeletal muscle and bone
causes: nutrient uptake and actual cell growth

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67
Q

what is the difference between direct and indirect GH effects?

A

direct: GH facilitates energy to be able to be used
indirect: GH uses IGFs to actually tell cells to grow

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68
Q
A
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69
Q

what is gigantism? cause by?

A

excessive overall growth due to too much GH before puberty

caused by pituitary tumor

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70
Q

what is acromegaly?

A

enlarged hands, feet, face caused by too much GH after puberty

caused by pituitary tumors

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71
Q

what is pituitary dwarfism? caused by?

A

overall small growth due to too little GH before puberty

caused by genetic mutations

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72
Q

what does ACTH stand for?
what cell type within the anterior pituitary releases ACTH?

A

adrenocorticotropic hormone
corticotropic cells

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73
Q

what hypothalamus hormone triggers ACTH release in anterior pituitary?
where does ACTH get released to?
what form of regulation is this?

A
  • corticotropin-releasing hormone (CRH)
  • released to adrenal cortex where then triggers release of corticosteroids
  • hormonal regulation
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74
Q

what is responsible for inhibiting ACTH? what is this an example of?

A

cortisol released from adrenal cortex
negative feedback

75
Q

when does CRH get released?

A
  • in the mornings due to circadian rhythm
  • stress
76
Q

what can too much ACTH cause?

A

symptoms associated with stress such as high blood pressure, low immune function

77
Q

what does TSH stand for?
what cell type in the anterior pituitary releases TSH?

A

thyroid-stimulating hormone
thyrotropic cells

78
Q

describe how TSH is regulated. what causes it to be released? what does it do when it is released?

A

thyroid releasing hormone (TRH) in the hypothalamus causes TSH to be released which then goes to thyroid and causes the thyroid to release thyroid hormone

hypothalamus -> TRH -> pituitary gland -> TSH -> thyroid -> thyroid hormone

79
Q

what cell type makes FSH and LH in the anterior pituitary?

A

gonadotropic cells

80
Q

what does FSH and LH stand for?

A

follicle stimulating hormone
luteinizing hormone

81
Q

what hypothalamus releasing hormone causes FSH and LH to be released?

A

gonadotropin-releasing hormone (GnRH)

82
Q

what does it mean when we say that the release of GnRH by the hypothalamus is pulsatile?

A

it is released in bursts (levels go up and down)

83
Q

constant high levels of GnRH causes what to happen?

A

gonadotropic cells to become unresponsive and no longer produce FSH and LH (chemical castration)

84
Q

what cell type produces and releases PRL in anterior pituitary?

A

prolactin cells

85
Q

what makes prolactin release different that the other anterior pituitary?

A

does not need releasing hormone from hypothalamus but instead requires drop in dopamine initiated by the hypothalamus

86
Q

what does PRL cause to happen?

A

triggers production of breast milk in females (no clear function in males)

87
Q
A
88
Q
A
89
Q
A
90
Q
A
91
Q

what gland is the largest pure endocrine gland in the body?

A

thyroid

92
Q

what is the small piece of tissue that connects both lateral lobes of the thyroid called?

A

isthmus

93
Q

what is the structure of thyroid follicles made of?

A

hollow spheres with outer edges made of epithelial cells and inner hollow center is colloid which contains thyroglobulin (protein used to make TH)

94
Q

what is found in the space between each of the hollow spheres of the thyroid follicles?

A

parafollicular cells (c cells) which produce calcitonin

95
Q

what is the protein that makes thyroid hormone?
what are the two types of thyroid hormone?

A

thyroglobulin
T3 and T4

96
Q

what is the name for T3 and T4?
which is potent?
which is most common?

A

T3: triiodothyronine (potent)
T4: thyroxine (most common)

97
Q

what is the effect of TH?

A

increased basal metabolic rate - makes all cells burn more energy which is important for neuronal development and prepubescent growth

98
Q

what causes TH to be released?

A

TSH from the pituitary which is released in response to TRH from the hypothalamus

99
Q

what inhibits TRH release? what is this called?

A

thyroid hormone circles back to inhibit TRH release
negative feedback

100
Q

what factors besides prepubescent growing would cause the release of TH?

A

other conditions that require increase energy requirements
(pregnancy/ cold temps)

101
Q

what is hypothyroidism in adults?

A

caused by low function of thyroid gland causing myxedema

102
Q

what are symptoms of myxedema?

A

swelling of mucus membranes
low metabolism (lethargic, chilled, mentally slow, constipated)

103
Q

what can hypothyroidism in children cause?

A

cretinism

104
Q

what is cretinism? what is it caused by?

A

hypothyroidism in children which results in permanent mental retardation and stunted growth

due to lack of iodine in food or soil (common in developing countries)

105
Q

where do most Americans get their iodine?

A

salt

106
Q

what is hyperthyroidism?

A

excessive function of thyroid gland resulting in wasting, nervousness, tremors

107
Q

what condition can cause hyperthyroidism? what would that look like?

A

Graves’ disease - autoimmune disease where antibodies mimic TSH
bug eyes (exophthalmos)

108
Q

what is a goiter?

A

noncancerous overgrowth of thyroid due to colloid build up

109
Q

what cell type releases calcitonin?

A

parafollicular cells (c cells)

110
Q

when is calcitonin released? what does calcitonin do?

A

is released in response to high blood calcium levels
lowers blood calcium levels by decreasing osteoclast activity so that more calcium ends up in the bones

111
Q
A
112
Q
A
113
Q
A
114
Q

what is the location of the parathyroid gland? how many of them are there?

A

somewhere posterior of the thyroid
most have 4
some people have 8

115
Q

when is parathyroid hormone released? what is the effect of parathyroid hormone?

A

is released when blood calcium levels are too low
functions to bring blood calcium levels up by either increasing osteoclast activity/ tells DCT to save more calcium/ tells gut to absorb more calcium

116
Q

what type of regulation is parathyroid hormone?

A

humoral

117
Q
A
118
Q
A
119
Q

what is the function of the adrenal cortex?

A

produces 3 types of corticosteroids

120
Q

what is the function of the adrenal medulla?

A

part of ANS
produces epinephrine/norepinephrine

121
Q

what are the three layers of the adrenal cortex in order of superficial to deep?

A

zona glomerulosa
zona fasciculata
zona reticularis

122
Q

what hormone does the zona glomerulosa produce?
what are those responsible for?
ex?

A

mineralocorticoids
regulates sodium reabsorption and potassium secretion in DCT
ex: aldosterone

123
Q

what would the release of aldosterone cause?

A

kidneys to save sodium and water which increases blood pressure

124
Q

what is aldosterone released in response to?

A

low blood sodium
high blood potassium
low blood volume/pressure

125
Q

what can hypersecretion of aldosterone cause?

A

water retention (edema)
hypertension
weakness (due to low potassium)

126
Q

what hormone does the zona fasciculata secrete?
what does it do?
example?

A

glucosteroids
increase blood sugar
ex: cortisol (stress hormone)

127
Q

what are the effects of cortisol on the body?

A

increased blood sugar
increased blood pressure
suppression of immune system
inhibits CRH release (negative feedback)

128
Q

what hormone does the zona reticularis make and secrete?
what does it do?
example?

A

gonadocorticoids
weak sex hormones
ex: androstenedione

129
Q

when is androstenendione present in the body?

A

during early puberty (preteen) before strong sex hormones of the gonads are made

130
Q

what are the effects of androstenedione?

A

hair growth in puberty
is the only source of estrogen after menopause

131
Q

what age is androstenedione released?

A

between age 7-13

132
Q

what can too much androstenedione cause?

A

in females: adrenogenital syndrome - push secondary male sexual characteristics in females
in males: promotes early onset puberty

133
Q
A
134
Q

what is the type of regulation of release is for aldosterone?

A

humoral (sodium levels)

135
Q

what is the type of regulation of release is for cortisol?

A

hormonal (ACTH)

136
Q

what is the type of regulation of release is for androsteindione?

A

neural (aging)

137
Q

what type of cells is the adrenal medulla made of? what is this similar to?

A

neuroendocrine cells
similar to posterior pituitary

138
Q

what hormone do the neuroendocrine cells in the adrenal medulla secrete?

A

epinephrine and norepinephrine

139
Q

thyroid hormones are tyrosine derived, what other hormones are like this? what does that mean for the receptor?

A

epinephrine and norepinephrine
receptors would be located inside the cells

140
Q

what is the ratio that epinephrine and norepinephrine is released?

A

80% epinephrine
20% norepinephrine

141
Q

what are the effects of epi/norepinephrine?

A

increase blood sugar
increase heart rate
increase blood pressure
increase metabolic rate
diverts blood from skin and gut to muscles and vital organs

142
Q

when is epinephrine/norepinephrine released? what kind of regulation is this?

A

short-term stressors
neural regulation

143
Q
A
144
Q
A
145
Q
A
146
Q

which endocrine organ also acts as an exocrine organ?

A

pancreas

147
Q

how does the pancreas act as an exocrine gland?

A

excrete digestive enzymes

148
Q

how does the pancreas act as an endocrine gland?

A

endocrine cells in the Islets of Langerhans called alpha cells and beta cells

149
Q

what type of hormone do alpha cells secrete in the Islets of Langerhans of the pancreas?

A

make glucagon (peptide hormone)

150
Q

where does glucagon target when it is released? why?

A

liver
to increase blood sugar by glycogenolysis and gluconeogenesis

151
Q

what are the other hormones that increase blood sugar besides glucagon?

A

cortisol
epinephrine/norepinephrine
growth hormone

152
Q

what is glycogenolysis?

A

breakdown of glycogen to glucose

153
Q

what two instances would glucagon be released? what type of regulation?

A

in response to low blood glucose (humoral)
in response to SNS (neural)

154
Q

what type of hormone do beta cells secrete in the Islets of Langerhans of the pancreas?

A

secrete insulin

155
Q

what effect does insulin have on the body

A

decreases blood sugar by activating insulin dependent glucose transport channels (GLUTs) in skeletal muscle and adipose tissue

156
Q

which is more common of the islet of langerhan cell types?

A

beta cells are most common

157
Q

which organs have insulin-independent GLUTs?

A

brain
liver
kidney

158
Q

when is insulin released?

A

in response to high blood sugar levels
in response to PNS

159
Q

what is diabetes mellitus?

A

occurs when blood glucose levels are too high
there is plenty of glucose in the blood but cells are not up-taking it so the body metabolizes proteins and fats instead

160
Q

what are symptoms of diabetes mellitus?

A

polyuria (excessive urination)
polydipsia (excessive thirst)
polyphagia (excessive hunger)

161
Q

what causes type 1 diabetes mellitus?

A

beta cells are killed by an autoimmune response so there is no insulin production

162
Q

what is type 1 diabetes treatment?

A

insulin injections
pancreatic islet cell transplants

163
Q

what causes type 2 diabetes mellitus?

A

due to chronic high blood sugar levels
which causes cells to become insulin resistant so they no longer uptake glucose into the cell (cell then starves)

164
Q

what is type 2 diabetes mellitus treatment?

A

diet and exercise
insulin injections (amplify signal)
medication to inhibit glucose absorption in intestines and glucose release by liver

165
Q
A
166
Q
A
167
Q
A

should decrease amount of sugar entering the blood so it should decrease blood sugar levels

168
Q

what is the correct term for sperm/eggs?

A

spermatocytes
oocytes

169
Q

what is copulation?

A

sex - delivery of male gametes into female reproductive tract

170
Q

during sex, what shape is the penis? how was this determined? who was wrong about their idea of what shape it was?

A

boomerang shape
MRI analysis determined its correct shape
Leonardo Da Vinci was wrong

171
Q

what is fertilization?
where does this occur usually?

A

when sperm and egg cells unite
in the ampulla of the uterine tube

172
Q

what is conceptus?

A

product of fertilization

173
Q

what is a conceptus called when it is 1-8 weeks old?
what is called after that?

A

embryo
then called fetus until birth

174
Q

where does implantation occur?

A

embryo attaches to uterine lining (endometrium)

175
Q

what is the difference between monozygotic and dizygotic twins?

A

mono: 1 fertilization event leads to two identical embryos
di: 2 separate fertilization events lead to non-identical embryos

176
Q

what is gestation?

A

support of embryonic and fetal development (occurs inside uterus)

177
Q

what is parturition? when does it occur?

A

birth
approx. 280 days from last menstrual cycle

178
Q
A
179
Q
A
180
Q
A
181
Q
A
182
Q

what happens to homologous chromosomes in meiosis 1?

A

homologous chromosomes separate

183
Q

what happens to sister chromatids in meiosis 2?

A

sister chromatids separate