quiz 2 sex hormones Flashcards
1
Q
androgens
A
hormones usually associated with men and maleness
2
Q
where are androgens also found
A
in women, but 8x less common
3
Q
where are androgens synthesized
A
in the adrenal glands in both sexes, ovaries of females and testes of males
4
Q
most common and most important androgen
A
testosterone
5
Q
all androgens are born out of what molecule
A
cholesterol
6
Q
all androgens are
A
steroids
7
Q
all androgens
A
need something to guide them through blood since not water soluble
8
Q
what does testosterone bind t in blood
A
sex hormone binding globulin so it can travel through blood
9
Q
when to androgens need to be released
A
at the onset of puberty
10
Q
what happens so androgens can be released
A
the hypothalamus begins to create and secrete the protein GnRH
11
Q
GnRH
A
gonadotropin-releasing hormone
12
Q
GnRH does what
A
leaves the hypothalamus and travels to the pituitary gland
13
Q
what does GnRH do at the pituitary gland
A
where it causes the secretion of a second protein hormone called LH
14
Q
LH
A
luteinizing hormone
15
Q
LH does what
A
leaves the pituitary gland and finds luteinizing hormone receptors
16
Q
where are luteinizing hormone receptors located
A
in Leydig cells in the testes
17
Q
Leydig cells begin what
A
the synthesis of testosterone
18
Q
what is the HPG axis
A
the hypothalamus, pituitary, gonad
19
Q
the HPG axis is the pathway the body uses….
A
to control sex hormone production
20
Q
testosterone will enter cells and find…
A
androgen receptors
21
Q
androgen receptors interact
A
with DNA to upregulate or downregulate at least 84 different genes (leads to many effects)
22
Q
wat does testosterone do in vitro
A
- high enough levels lead to formation of the penis and gonads
- leads to masculinization or feminization of the brain even more than levels once the fetus reaches adulthood
23
Q
wat does testosterone do in puberty
A
- leads to an increase in muscle mass
- leads to an increase in bone mineral density
- leads to formation of body hair, acne
24
Q
wat does testosterone do in adults
A
- leads to the formation of sperm in males
- leads to increased sex drive (both sexes)
- romance, fatherhood leads to decreased testosterone levels
25
anabolic steroids
injecting or ingesting chemicals that are testosterone or are very chemically similar. banned in most sports
26
farquharson phenomenon
body adjusts to new levels of androgens and stops producing its own. once doping stops, body produces far too little testosterone
27
castrati
male singers who were castrated before onset of puberty
28
what happens to castrati
voices never dropped, so they could sing very high ranges.
29
what else happens to castrati
their epiphyseal plates never hardened, so their bones (ribs) grew longer
30
low T
testosterone levels begin to drop slowly after the age of 30, in some more than others
31
what is normal range of testosterone
300-1000 ng/dl
32
extreme case of low t are called
andropause or male menopause
33
what happen be given to treat low T
testosterone supplements through the skin or in a transplant
34
is a estrogen a hormone
no its a class of hormones (like androgen)
35
what are the three most important estrogens
estradiol, estrone, estriol
36
estradiol
most common estrogen during reproductive years (menarche to menopause)
37
estrone
most common estrogen after menopause
38
estriol
most common estrogen during pregnancy
39
estrogens are primarily
found in women, but are also in men at lower rates
40
potency of estradiol
100%
41
potency of estrone
33%
42
potency of estriol
1.6%
43
estradiol levels...
vary widely through the menstrual cycle
44
estrogens all
come from cholesterol
45
estrogens can all
enter cells but are not water soluble
46
what does estrogen also bind to in blood
sex hormone binding globulin (same as androgens)
47
testosterone can be broken
down into estrogens
48
estrogens follow a similar
release pattern to androgens
49
what is the release pattern of estrogens ( first step )
GnRH is made, which causes LH to be made
50
in females where does LH bind to
receptors on granulosa cells in the ovaries which causes estrogens (estradiol) to be synthesized and secreted
51
the estrogen pathway happens in
HPG AXIS
52
estrogens bind to a variety of
estrogen receptors
53
what can estrogen binding to estrogen receptors do
- formation of breast
- slowed height increase in puberty
- slowed bone resorption less osteoclast activity: RANK pathway)
- regulation of the mentrual cycle (along w/ other hormones)
54
what is estrogen necessary for in men
the production of sperm
55
what are contraceptives
pills with synthetic estrogens that mimic estradiol and cause irregular estrogen levels
56
breast cancer..what does estrogen do
most cases are E-R positive, meaning that the presence of estrogen causes the cancer to grow faster
57
gynecomastia (what does estrogen do)
the formation of mall breasts in men.
58
when does gynecomastia happen
common (70%) in puberty and in later life
59
other non-estrogen hormones that are crucial to women's reproduction
LH, FSH, progesterone
60
what does LH do in women
stimulates granulosa cells to produce estrogens, required for ovulation to occur
61
FSH
follicle-stimulating hormone
62
FSH function
another protein hormone that is also essential for ovulation
63
what is progesterone
a steroid released late in the mesntrual cycle
64
what does progesterone do
causes mucus levels to thicken in the uterus and allow for a potential zygote to stick
65
what does progesterone inhibit
the production of GnRH, meaning that LH and estradiol levels will decrease
66
progesterone is
a precursor to the estrogens (and androgens)
67
the journey from cholesterol to sex hormones
cholesterol, progestagens, androgens, estrogens
68
the female reproductive hormones work to regulate each other
in negative or positive feedback loops
69
levels of estradiol, FSH, progesterone
...vary across the menstrual cycle
70
how to contraceptives work
```
trick the body into thinking progesterone levels
are high (and sometimes alter levels of estrogens to)
```
71
what would the presumed high levels of progesterone do w/ contraceptives
stop GnRH from being produced, which stops both LH and estradiol from being made
72
endocrine is the opposite of the
nervous system
73
endocrine and nervous system both
transmit signals around the body
74
the nervous system is built on
speed
75
the endocrine system is ____ and always uses
slower, hormones
76
there are about _____ distinct hormones in the human body
50
77
what are the three classes of hormones
amino acid derivatives
proteins
steroids
78
depending on the type the _____ of a hormone can be different
mechanism
79
what is a mechanism
how a chemical causes its desired effect
80
steroids are al synthesized from the molecule ____
cholesterol
81
steroids all look like
cholesterol
82
what do steroids usually end in
ol or one
83
what are hormones that are proteins
long chains of amino acids
84
hormones that are proteins are significantly
larger than other hormones and water-soluble
85
amino acid derivatives are synthesized from
various amino acids
86
what do amino acid derivatives look like
they are small and look like amino acids
87
what would amino acids (amino acid derivatives) look like
short chains of carbon
88
examples of amino acid derivatives
tyrosine, epinephrine
89
example of a protein that is a hormone
insulin
90
where are hormones created
in glands located around the body
91
where are hormones secreted
into the bloodstream, where they travel to their intended target target
92
steroids are not what? why ?
water-soluble, because they are made from cholesterol which is a lipids
93
what do steroids require to travel through blood
a transport protein
94
if amino acid derivatives are non polar they
need transport proteins
95
steroid hormones and most non polar amino acid derivatives are capable of what
passing through a cell's membrane
96
once inside, steroid hormones and non polar amino acid derivatives do WHAT?
bind to receptors and form a hormone-receptor complex
97
what does the hormone receptor complex do
enters the nucleus and causes upregulation or downregulation of proteins
98
nonsteroid hormones and polar amino acid derivatives CANNOT..
pass through a cell's membrane
99
to _____ nonsteroid hormones must
send signals to the cell, bind to a receptor on the cell's membrane
100
a membrane receptor activated by a nonsteroid hormone
causes other molecules in the cell to invoke some kind of change
101
what are the most important hormones the thyroid produces
T4 and T3
102
T4
thyroxine
103
T3
triiodothyronine
104
T3 and T4 are jointly involved in
regulating cellular energy processes around the body
105
differences between T3 and T4
T4 has one more iodine
106
the thyroid is what percentage T4
80%
107
the thyroid is what percentage T3
20%
108
inside cells T4 is
converted to T3 (only one active in cells)
109
when are T3 and T4 made
when the pituitary gland secretes TSH
110
why do we even have T4
more stable in bloodstream
111
TSH
thyroid stimulating hormone
112
T4 and T3 are
derivatives of amino acid tyrosine, but have been combined with iodine
113
once secreted, what do T4 and T3 do
bind to the transport protein TBG and travel through blood
114
TBG
thyroxine-binding globulin
115
know thyroid gland
ok
116
goiter
an enlarged thyroid gland (developing countries)
117
what happens right after T3 and T4 enter the cell
T4 is converted to T3, T3 passes through the nuclear membrane and binds to TR
118
TR
thyroid hormone receptor
119
what happens without T3
the thyroid receptor binds to DNA and blocks certain genes from being expressed
120
the newly expressed genes because of T3 binding to Tr and moving it off DNA do...
increase the rate of cellular metabolism in cells all across the body
121
hyperthyroidism
when the thyroid makes too many hormones
122
hypothyroidism
is when the thyroid does not make enough hormones
123
PTH is made by
chief cells in the parathryoid glands
124
PTH is made in response to
low blood calcium leels (hypocalcemia)
125
PTH is a
protein
126
what does T3 do
bins and causes TR to move ff DNA, allowing those genes to be expressed
127
PTH binds to
parathyroid hormone receptors on the outer membranes of osteoblasts and osteoclasts
128
PTH causes
osteoblasts to slow down
osteoclasts to speed up
.... releasing more calcium from bone and into the blood
129
PTH is made of how many amino acids
84 (kinda small)
130
PTH also binds to....
receptors on the kindeys
131
PTH causes what on the kidneys
upregulation of an enzyme from a gene on DNA which converts calcidiol into Vitamin D
132
when is Vitamin D synthesized
when PTH sends a signal to the kidneys
133
vitamin D is also a what
hormone
134
what do people say is only partly true
that sunlight gives you Vitamin D
135
vitamin D is what kind of hormone
a steroid hormone since it is synthesized from cholesterol
136
what does sunlight directly cause
cholesterol to be converted into cholecalciferol in the skin
137
cholecalciferol.....
converted into calcidiol in the liver
138
calcidiol...
converted into vitamin D in the kidney
139
Vitamin D.....
attaches to vitamin d binding protein in the blood because it is not water soluble
140
once Vitamin D is in the blood
it travels until it finds and binds to a Vitamin D receptor
141
where are vitamin D receptors located
in the nucleus of small intestine cells
142
vitamin D and vitamin D receptor form
a hormone-receptor complex
143
what does the hormone-receptor complex of vitamin D and vitamin d receptor do
binds to DNA and causes increased expressions of protein calbindin
144
calbindin
a channel in the membrane of small intestine that allows calcium to enter and be digested
145
with more vitamin D
calcium levels increase
146
rickets
disease when there is a lack of vitamin D, phosphorus and calcium that results in soft, weak bones
147
myxedema
caused by the under-activity of thyroid gland during adulthood, causes weight gain
148
cretinism
under-secretion of T3 and T4 during infancy and fetal life
149
grave's disease
hyposecretion of thyroid hormones, leads to weight loss
150
ghrelin
a protein hormone
151
what is ghrelin made by
cells in stomach and hypothalamus
152
what does ghrelin do
stimulate hunger and GH release
153
GH
growth hormone
154
what did they do for the ghrelin study
had 6 people fast, took their blood every 20 minutes
155
ghrelin study concluded
when your brain says its meal time ghrelin is released, (spikes in graph at meal time)
156
circadian tosis
you train yourself to eat at certain times of the day
157
BMI ghrelin
spikes at similar times but people with higher BMI had more ghrelin
