Repro Physiology Dr. Ottobre

Front 1

The hypothalamus in inherently...

Back 1

Female

Front 2

Which hormone defeminizes the hypothalamus during embryogenesis?

Back 2

Testosterone

Front 3

Which center of the hypothalamus is not developed in the male?

Back 3

Surge Center

Front 4

In order for the testosterone in the testis to defeminze the hypothalamus it must be converted to?

Back 4

Estradiol

Front 5

Why doesn't the female hypothalamus become de-feminized?

Back 5

Estradiol from the ovaries can not cross the blood brain barrier

Front 6

Which protein binds estradiol to prevent is from crossing the blood-brain barrier?

Back 6

Alpha-fetoprotein

Front 7

Testosterone can cross the blood-brain barrier T/F?

Back 7

True

Front 8

If bulls are castrated at or near birth they will have some ability to secrete a

Back 8

GnRH surge

Front 9

In a postpubatal male LH does not surge but instead has a

Back 9

Pulsatile pattern of secretion

Front 10

Puberty is defined as

Back 10

ability to accomplish reproduction successfully

Front 11

The fundamental requirement for puberty is

Back 11

secretions of GnRH at the appropriate frequency and quanities to stimulate gonadotropin release by the pituitary

Front 12

The limiting factor for pubertal onset appears to be the aility of presynaptic neurons to transmit information to the...

Back 12

GnRH neurons

Front 13

3 ways to define puberty in the female

Back 13

Age at first estrus

Age at first ovulation
Age at which a female can support a pregnancy without detrimental effects

Front 14

The first ovulation in ewes and heifers is generally not accompanied by behavioral estrus and is called

Back 14

"Silent ovulation"

Front 15

4 ways to define puberty in males

Back 15

Age when behavioral traits are expressed

Age at first ejaculation

Age when spermatozoa first appear in the ejaculate

Age when the ejaculate contains a threshold number of spermatazoa

Front 16

The first ejaculation substantially precedes the ability to produce

Back 16

sufficient spermatazoa to achieve fertilization

Front 17

After an LH episode in the male __________ is released shortly after

Back 17

Testosterone

Front 18

4 External factors that influence the timing of puberty

Back 18

Season during which the animal is born

Photoperiod

The presence or absence of the opposite sex
The density of the groups in which animals are housed

Front 19

In a prepubital animal the anterior lobe of the pituitary will secrete FSH and LH if stimulated y exogenous...

Back 19

GnRH

Front 20

When the prepubital female is stimulated by FSH and LH the ovaries will

Back 20

Produce follicles and estradiol

Front 21

The major factor that limits the onset of puberty

Back 21

Not enough of GnRH secreted from the hypothalamus to cause gonadotropin release

Front 22

Development of the hypothalamus develops _________ over growth period of the animal

Back 22

Gradually

Front 23

Before ovulation can occur in the female full neural activity of the _________ __________ must be acheived

Back 23

Surge Center

Front 24

Even though the neurons in the surge center in prepubatal female are sensitive to estradiol they cannot secrete much GnRH because _________ is too low

Back 24

Estradiol

Front 25

The frequency of GnRH pulses in the prepubertal female is much ________ than that of postbubertal female

Back 25

Lower

Front 26

LH pulses are apparent in which stage of puberty for the female? Post/Pre?

Back 26

Both

Front 27

Prior to puberty, low-frequency GnRH pulses provide insufficient stimuli to cause

Back 27

the anterior lobe to release LH and FSH at high levels

Front 28

Estradiol remains below the minimum threshold is prepubertal female because

Back 28

There is no stimulation from LH or FSH from follicles

Front 29

In the male, onset of puberty is brought about because of decreased hypothalamic sensitivity to __________ ___________ by testosterone/estradiol

Back 29

Negative Feedback

Front 30

After puberty males on use a negative/positive feedback system

Back 30

Negative

Front 31

As puberty draws nearer in males the GnRH neurons become more/less sensitive to testosterone and estradiol

Back 31

Less

Front 32

Due to decreased sensitivity to negative feedback the hypothalamus can secrete more and more GnRH and thus more and more ___ and ___ to stimulate the testis

Back 32

FSH, LH

Front 33

In the prepubertal female the surge center is quite sensitive to the positive feedback of estradiol. However, the surge center cannot release "ovulatory quantities" of GnRH because the ovary cannot secrete high levels of...

Back 33

estradiol

Front 34

Tonic center is sensitive to ______ feedback
Surge Center is sensitive to ______ feedback

Back 34

Negative
Positive

Front 35

During the pubertal transition in the female the negative feedback sensitivity by the tonic center to estradiol decreases and causes higher amounts of _____ to be secreted which in turn causes an increase in pulse frequency of ___

Back 35

GnRH, LH

Front 36

Increased pulse frequency of LH cause the ovaries to release more and more ______

Back 36

Estradiol

Front 37

Threshold level of estradiol causes

Back 37

The surge center to release a massive discharge of GnRH

Front 38

Sensitivity to positive feedback on the surge center remains _______ during the life of the animal

Back 38

Unchanged

Front 39

It is the decreased sensitivity to positive/negative feedback that triggers the onset of puberty

Back 39

Negative

Front 40

Hypothalamic neurons that regulate GnRH secretion detect "moment-to-moment" changes in blood _________ and ______ ______

Back 40

Glucose, fatty acids

Front 41

A hormonal peptide that is secreted by adipocytes

Back 41

Leptin

Front 42

Amount of leptin in the blood is directly related to the amount of ___ in the body

Back 42

Fat

Front 43

Pigs housed in large groups (10+) have _________ puberty

Back 43

Normal

Front 44

Pigs housed in small groups (2-3) have ________ puberty

Back 44

Delayed

Front 45

Gilts exposed to a boar have _______ puberty

Back 45

Accelerated

Front 46

In the queen increased __________ prompts the onset of puberty

Back 46

Photoperiod

Front 47

Reproductive cyclicity consists of which two cycles?

Back 47

Menstrual and Estrous

Front 48

If a word ends in -ous it is a/an _____
If a word ends in -us it is a/an _____

Back 48

Adjective

Noun

Front 49

_______ is a period of sexual receptivity

Back 49

Estrus

Front 50

3 examples of polyestrus

Back 50

Cattle

swine

rodents

Front 51

Estrous cycle type having a uniform distribution of cycles throughout the year

Back 51

Polyestrus

Front 52

Display "clusters" of estrous cycles that occur only during a certain season of the year

Back 52

Seasonally polyestrus

Front 53

3 examples of seasonally polyestrus

Back 53

Sheep, goat, mare

Front 54

Have one cycle per year

Back 54

Monoestrus

Front 55

3 examples of monestrus

Back 55

Wolf, dog, fox

Front 56

The follicular phase is the period from the regression of the ________ ________ to _________

Back 56

Corpus lutea, ovulation

Front 57

The follicular phase only account for ___% of the estrous cycle

Back 57

20

Front 58

During the follicular phase of the estrous cycle the primary hormone secreted is ______? And the primary ovarian structure is _____?

Back 58

Estradiol, Large antral follicles

Front 59

During the luteal phase of the estrous cycle the primary hormone secreted is ________? And the primary ovarian structure is ______?

Back 59

Progesterone, CL

Front 60

Proestrus and estrus are part of the _________ phase

Back 60

Follicular

Front 61

Metestrus and diestrus are part of the _________ phase

Back 61

Luteal

Front 62

Follicular phase of the estrous cycle has high/low estrogen and low/high progesterone

Back 62

High, low

Front 63

Luteal phase of the estrous cycle has high/low estrogen and high/low progesterone

Back 63

low, high

Front 64

Proestrus begins when _______ declines due to leuteolysis

Back 64

progesterone

Front 65

Proestrus is definied as the period of progesterone dominance to _______ dominance

Back 65

estradiol

Front 66

Proestrus lasts _____ days

Back 66

2-5

Front 67

Proestrus = _______ + ________

Back 67

Formation of ovulatory follicles, estrogen

Front 68

Estrus = ________ + _________

Back 68

sexual receptivity, peak estrogen secretion

Front 69

Metestrus = ________ + _________

Back 69

CL formation, beginning of progesterone secretion

Front 70

Diestrus = _________

Back 70

sustained luteal secretion of progesterone

Front 71

The longest period of the estrous cycle

Back 71

Diestrus

Front 72

Estrus is the period in which the female allows _______

Back 72

Copulation

Front 73

Metestrus is period between ______ and the functional _____________ ___________

Back 73

Ovulation, corpus lutea

Front 74

The drop in blood FSH that occurs during proestrus is presumably due to _____ _______ on FSH by _______ secreted from developing follicles

Back 74

Negative feedback, inhibin

Front 75

Queens remain in a constant follicular phase until copulation this phase is called

Back 75

Postestrus

Front 76

Estrus behavior in the dog begins after ________ declines and ________ rises

Back 76

Estrogen, progesterone

Front 77

Diestrus in dogs lasts ___ months

Back 77

2

Front 78

Diestrus in the dog is a period of _______ ________

Back 78

luteal function

Front 79

The queen is only reception to mating during

Back 79

estrus

Front 80

Estrous cycles do not occur during pregnancy because elevated progesterone from the corpus luteum exerts negative feedback to inhibit ____ secretion

Back 80

GnRH

Front 81

Low melatonin secretion results in ___ frequency of pulses from the tonic center in short-day breeders

Back 81

Low

Front 82

Low melatonin secretion results in ____ frequency of pulses from the tonic center in long-day breeders

Back 82

High

Front 83

The events that occur between the onset of two successive menstrual periods

Back 83

Menstrual cycle

Front 84

What does bleeding form the vulva of the dog indicate

Back 84

Proestrus

Front 85

What hormonal pattern leads to estrous behavior in dogs?

Back 85

Peak estradiol, LH, FSH
Progesterone increases at the later half of estrus

Front 86

Which gland located in the brain plays a role in the regulation of seasonal breeding? Which hormone does this release?

Back 86

Pineal gland, melatonin

Front 87

How does melatonin effect seasonal breeders?

Back 87

An increase in daylight excites the retinal neurons that then activate the inhibitory neuron that decreases melatonin from the pineal gland

Front 88

How does menstrual cycle differ form the estrous cycle?

Back 88

No defined period of sexual receptivity

A period of endometrail sloughing called menses

The timeline for description of the cycle begins with menses not ovulation or estrus

Front 89

Follicular phase in menstrual cycle is __%

Back 89

50

Front 90

What is the effect of estrogen on the endometrium? Progesterone?

Back 90

Estrogen causes an increase thickness of the endometrium, progesterone increases it further

Front 91

The "driving force" for the follicular phase

Back 91

Luteolysis

Front 92

Negative feedback by estrogen and inhibin during the follicular phase. Where do they act? What is their effect?

Back 92

Ant pit, when serum inhibin (produced from the follicles as they develop) is high enough it causes a decrease in FSH

Front 93

Discuss positive feedback of estrogen during the follicular phase. Where does it act? What is the effect?

Back 93

surge center, increases the frequency of GnRH pulses

Front 94

How can estrogen have positive and negative feedback?

Back 94

Estrogen inhibits LH and FSH secretion from the ant pit but it stimulates GnRH release in the surge center

Front 95

Step 1 hormonal changes follicular phase
Serum progesterone declines as the _______ _______ regresses

Back 95

Corpus luteum

Front 96

Step 2 hormonal changes follicular phase

Reduced _______ feedback of progesterone on the ___________ and anterior pituitary

Back 96

Negative, hypothalamus

Front 97

Step 3 hormonal changes follicular phase

Gondaotropins begin to _____ and stimulate _____ production

Back 97

rise, estrogen

Front 98

Step 4 hormonal changes follicular phase

When serum estrogen exceeds the threshold it triggers a _______ feedback

Back 98

positive

Front 99

Step 5 hormonal changes follicular phase

When there is a positive feedback from serum estrogen reaching its threshold there is an ____ surge

Back 99

LH

Front 100

Step 6 hormonal changes follicular phase

The LH surge induces _____ and _____ of the dominant follicles

Back 100

ovulation, leutinization

Front 101

Follicle made of a single layer of squamous cells

Back 101

Primordial follicle

Front 102

Follicle made of a single layer of cuboidal granulosa cells

Back 102

Primary follicle

Front 103

What is a zona pellucida?

Back 103

tough outer covering of the follicle

Front 104

Oocyte cell membrane

Back 104

vitelline membrane

Front 105

Layer of cells outside the granulosa cells

Back 105

Theca interna

Front 106

Definition of antrum

Back 106

portion of the follicle filled with follicular fluid

Front 107

Which follicle stage has developed an antrum?

Back 107

Tertiary

Front 108

Which follicle stage has developed a zona pellucida?

Back 108

Secondary

Front 109

When has the oocyte reached its maximum size

Back 109

Tertiary follicle

Front 110

Definition of cumulus oophorus

Back 110

Granulosa cells that form a hill and surround oocyte

Front 111

To what stage can a follicle progress in the absence of hormones form the ant pit?

Back 111

secondary

Front 112

FSH is needed for antral follicle growth T/F?

Back 112

True

Front 113

Oocytes at which phase are housed in tertiary follicles?

Back 113

secondary oocytes

Front 114

The LH surge triggers resumption of the first meiotic division in oocytes housed in

Back 114

Dominant follicles

Front 115

In preselection follicles (i.e., prior to selection to become dominant follicles), LH receptors are located on

Back 115

Thecal cells only

Front 116

In dominant, preovulatory follicles, LH receptors are located on

Back 116

Thecal and granulosa cells

Front 117

When serum estrogen exceeds a threshold concentration in the presence of low serum progesterone in the sheep

Back 117

Stimulates GnRH from the surge center

Front 118

If the uterus is removed from a rhesus monkey, then the life span of the corpus luteum will

Back 118

stay the same

Front 119

Which of the following treatments, if administered on day 10 of the estrous cycle, will result in luteal regression in the cow in two or three days?

Back 119

An injection of PGF-alpha 2

Front 120

Cell type that gives rise to large and small luteal cells?

Back 120

Thecal and granulosa cells

Front 121

A CIDR (controlled internal drug release) device that is charged with progesterone is inserted into the vagina of a non-pregnant cow on day 10 of the estrous cycle. Recall that the estrous cycle in the cow averages about 21 days in length. The CIDR is left in the cow for 20 days. Which of the following events do you predict will likely occur within two or three days following removal of the CIDR 20 days after it was inserted.

Back 121

The cow will come in to estrus

Front 122

A sheep had a single ovulation on the left ovary, so she has a single corpus luteum on the left ovary. Predict the results of removal of the left uterine horn early in the estrous cycle.

Back 122

Corpus luteum would regress after 35 days

Front 123

Transdermal delivery of progesterone and estrogen is an option available for human contraception. A patch is applied to the skin, and will deliver hormone for seven days. The system calls for wearing one patch for seven days, replacing that with a second patch for the next seven days, and replacing that with a third patch for seven more days. This is followed by seven patch-free days. This 28 day sequence is then repeated as long as contraception is desired. Using this system, when does menstruation begin?

Back 123

After the removal of the 3rd patch

Front 124

FSH surges to recruit the _________ _____, then FSH drops and remains low until it surges again with LH prior to ________

Back 124

preovulatory wave, ovulation

Front 125

At what stages can follicles undergo atresia?

Back 125

Any

Front 126

Follicles with high number of LH receptors become

Back 126

preovulatory follicles

Front 127

Primordial germ cells divide mitotically into

Back 127

oogonia

Front 128

Oogonia divide into

Back 128

Primary oocyte

Front 129

Primary oocyte undergo meiosis to form

Back 129

2N primary oocyte

Front 130

How many divisions are there in meiosis?

Back 130

2, 4 haploid cells

Front 131

How many divisions are there in mitosis?

Back 131

2, 2 diploid cells

Front 132

Which 3 events are triggered by the LH surge?

Back 132

First meiotic division, ovulation, leutinization

Front 133

Luteal phase lasts form time of _______ to ______ ________

Back 133

ovulation, luteal regression

Front 134

Degradation of the basement membrane is caused by an ___ surge

Back 134

LH

Front 135

Granulosa cells give rise to ______ luteal cells

Back 135

Large

Front 136

Thecal cells give rise to _____ luteal cells

Back 136

small

Front 137

Hypothalamus has _________ feedback of progesterone on ______ ________

Back 137

negative, GnRH secretion

Front 138

In the surge center progesterone prevents __ _____ and thus blocks ovulation

Back 138

LH surge

Front 139

What must be gone in order to have a functional preovulatory follicle?

Back 139

Corpus luteum

Front 140

In the tonic center progesterone _________ GnRH pulse frequency and pulse amplitude

Back 140

reduces

Front 141

In the anterior pituitary there is a negative feedback of progesterone on __ and ___

Back 141

LH, FSH

Front 142

Progesterone promostes ______ development to prepare the pregnant animal for lactation

Back 142

alveolar

Front 143

LH stimulates luteal ________ production

Back 143

progesterone

Front 144

If you take the uterus out of a farm animal what happens to the corpus luteum?

Back 144

Stays longer

Front 145

If you take the uterus out of a primate what happens to the corpus luteum?

Back 145

Remains the same

Front 146

The luteolytic signal comes from the _____ in farm animals

Back 146

uterus

Front 147

Luteolytic signal in primates comes from the ________ _________

Back 147

corpus luteum

Front 148

Which animal is more sensitive to prostaglandin (PGF-2alpha)?

Back 148

Horses

Front 149

If you remove the uterine horn without the corpus luteum what happens?

Back 149

Nothing, corpus luteum has same lifespan

Front 150

If you remove the uterine horn without the corpus luteum what happens?

Back 150

CL lasts twice as long

Front 151

If you take both uterine horns out what happens?

Back 151

CL lasts the length of pregnancy since there is no uterus to give signal to regress

Front 152

The process whereby cells of the ovulatory follicle are transformed into luteal tissue

Back 152

Luteinization

Front 153

Mixed thecal and granulosa cells of the corpus luteum produce which hormone

Back 153

progesterone

Front 154

Increase in corpus luteum size and weight is due to threefold increase in ________ of large luteal cells

Back 154

volume

Front 155

Increase in the corpus luteum size and weight is due to increase in ______ of small luteal cells

Back 155

number

Front 156

Two target components of the uterus from progesterone

Back 156

Glandular endometrium

Muscular myometrium

Front 157

Progesterone exerts a strong ________ feedback on the ________

Back 157

Negative

Hypothalamus

Front 158

How is prostaglandin transported from the uterus to the ovary?

Back 158

vascular countercurrent exchange mechanism

Front 159

Hormone that stimulates prostaglandin

Back 159

Oxytocin