ANSC 333 Exam 2
What are the two centers located in the hypothalamus? - ANS-tonic and surge
Males do not have a ___ center. - ANS-surge (happened during fetal development)
Protein that when bound, can't cross the blood-brain barrier resulting in the
development of the surge center - ANS-alpha-fetoprotein
___ does not bind to alpha fetal protein so it can cross the blood-brain barrier? -
ANS-testosterone
___ is hard to measure in circulation and ___ is easy to measure in circulation. -
ANS-GnRH and LH
___ is a proxy for GnRH. - ANS-LH
Some activity in gonads and hypothalamus occurs before ? - ANS-puberty
A continuous pulse of GnRH is released very 4-6 hours when? - ANS-puberty is
reached
What are the 4 things that control the age of which an individual attains puberty? -
ANS-genetics, acute nutrition (short-term nutrition), long-term nutrition, social
environment, photo-period (season)
Where does the primary adipose deposition occur in females? - ANS-mammary glands
___ breeds attain puberty at a younger age than ___ breeds. - ANS-maternal and
paternal
Define puberty. - ANS-the ability to accomplish reproduction successfully
Accumulation of fat; body composition; nutritional reserves that mom can draw from as
baby grows; if we feed more or higher quality feed we obtain higher percentages of fat -
ANS-long-term nutrition
We want heifers at ___% of their mature BW by the time they attain puberty? -
ANS-60-65
, Control GnRH by obtaining signals from multiple sources (FA's, etc.) when it is ideal to
start cycling; if one signal is off, the whole message to start is delayed/absent -
ANS-kisspeptin neurons
The number of animals in a group can alter the age at which they attain puberty;
pheromones are a big part (presence of a male) - ANS-Social environment
Affects sheep; most lamb in the spring time; natural breeding season is in the fall (they
can be big enough and fat enough, but if the season is not right for their system they
won't breed ---> negative impact on hypothalamus) - ANS-Photo-period (season)
Many cycles throughout the year (ex: cow, queen, rodents) - ANS-polyestrus
Mares are _________ breeders - ANS-seasonal (long day)
Small ruminants, such as sheep are ___ breeder. - ANS-seasonal (short day)
Want to have offspring when? - ANS-nutrition is plentiful to support lactation
One cycle per year - ANS-monoestrus (ex: dog, wolf, bear, fox)
Two phases of estrous cycle - ANS-follicular phase and luteal phase
The follicular phase begins immediately after? - ANS-luteolysis
Characterized by the conversion of corpus luteum to corpus albican and formation of
developing follicles. - ANS-follicular phase
Describe the early follicular phase - ANS-luteolysis results in a rapid decrease of
progesterone, this increases GnRH pulse frequency, causing FSH and LH to secreted
stimulating ovarian follicle growth and production of estrogen
Describe the late follicular phase - ANS-follice(s) secrete inhibin and estrogen,
producing a negative feedback on the pituitary's secretion of FSH
The follicular phase ends when? - ANS-estrogen reaches peak threshold concentrations
causing the surge center to release large amounts of GnRH, inducing the preovulatory
LH surge which results in ovilation of dominant follice
What are the two centers located in the hypothalamus? - ANS-tonic and surge
Males do not have a ___ center. - ANS-surge (happened during fetal development)
Protein that when bound, can't cross the blood-brain barrier resulting in the
development of the surge center - ANS-alpha-fetoprotein
___ does not bind to alpha fetal protein so it can cross the blood-brain barrier? -
ANS-testosterone
___ is hard to measure in circulation and ___ is easy to measure in circulation. -
ANS-GnRH and LH
___ is a proxy for GnRH. - ANS-LH
Some activity in gonads and hypothalamus occurs before ? - ANS-puberty
A continuous pulse of GnRH is released very 4-6 hours when? - ANS-puberty is
reached
What are the 4 things that control the age of which an individual attains puberty? -
ANS-genetics, acute nutrition (short-term nutrition), long-term nutrition, social
environment, photo-period (season)
Where does the primary adipose deposition occur in females? - ANS-mammary glands
___ breeds attain puberty at a younger age than ___ breeds. - ANS-maternal and
paternal
Define puberty. - ANS-the ability to accomplish reproduction successfully
Accumulation of fat; body composition; nutritional reserves that mom can draw from as
baby grows; if we feed more or higher quality feed we obtain higher percentages of fat -
ANS-long-term nutrition
We want heifers at ___% of their mature BW by the time they attain puberty? -
ANS-60-65
, Control GnRH by obtaining signals from multiple sources (FA's, etc.) when it is ideal to
start cycling; if one signal is off, the whole message to start is delayed/absent -
ANS-kisspeptin neurons
The number of animals in a group can alter the age at which they attain puberty;
pheromones are a big part (presence of a male) - ANS-Social environment
Affects sheep; most lamb in the spring time; natural breeding season is in the fall (they
can be big enough and fat enough, but if the season is not right for their system they
won't breed ---> negative impact on hypothalamus) - ANS-Photo-period (season)
Many cycles throughout the year (ex: cow, queen, rodents) - ANS-polyestrus
Mares are _________ breeders - ANS-seasonal (long day)
Small ruminants, such as sheep are ___ breeder. - ANS-seasonal (short day)
Want to have offspring when? - ANS-nutrition is plentiful to support lactation
One cycle per year - ANS-monoestrus (ex: dog, wolf, bear, fox)
Two phases of estrous cycle - ANS-follicular phase and luteal phase
The follicular phase begins immediately after? - ANS-luteolysis
Characterized by the conversion of corpus luteum to corpus albican and formation of
developing follicles. - ANS-follicular phase
Describe the early follicular phase - ANS-luteolysis results in a rapid decrease of
progesterone, this increases GnRH pulse frequency, causing FSH and LH to secreted
stimulating ovarian follicle growth and production of estrogen
Describe the late follicular phase - ANS-follice(s) secrete inhibin and estrogen,
producing a negative feedback on the pituitary's secretion of FSH
The follicular phase ends when? - ANS-estrogen reaches peak threshold concentrations
causing the surge center to release large amounts of GnRH, inducing the preovulatory
LH surge which results in ovilation of dominant follice
