Reproductive Endocrinology

Question 1

What is a simple neural reflex?

Answer 1

Nerves that release simple neurotransmitters directly onto the target tissue.

Question 2

What is a neuroendocrine reflex?

Answer 2

Needs a neurohormone to enter blood and act at a remote location.

Question 3

What is the neural control center for repro hormones?

Answer 3

Hypothalamus/pituitary

Question 4

What organ deposits neurohormones directly into circulation?

Answer 4

Posterior pituitary

Question 5

What regulates GnRH?

Answer 5

Male: Tonic center
Female: Tonic and Surge centers

Question 6

What quantity of repro hormones do you need?

Answer 6

Small quanitities

Question 7

How long are repro hormone half-lives?

Answer 7

Short

Question 8

Where does GnRH come from?

Answer 8

Hypothalamic nuclei

Question 9

Where do FSH, LH and prolactin come from?

Answer 9

Anterior Pituitary

Question 10

Where does Oxytocin come from?

Answer 10

Posterior pituitary

Question 11

Which repro hormones are a peptide?

Answer 11

GnRH

Question 12

Which repro hormones are a glycoprotein?

Answer 12

FSH
LH
Inhibin

Question 13

Which repro hormones are steroids?

Answer 13

Progesterone
Testosterone
Estradiol

Question 14

What does PGF2a do?

Answer 14

Lyses the corpus luteum

Question 15

What does PGE2 do?

Answer 15

Relaxes the cervix

Question 16

How do protein hormones cause their actions?

Answer 16

Bind to plasma membrane bound receptors

Question 17

How do steroid hormones cause their actions?

Answer 17

Travel freely through the plasma membrane into the cytoplasm and bind to the specific nuclear receptors

Question 18

What does binding of hormones result in?

Answer 18

New protein synthesis

Question 19

What are two functions of pheromones?

Answer 19

Influence the onset of puberty

Lets the male know who is in heat

Question 20

What 4 things affect the strength of a hormone?

Answer 20

Pattern and duration of secretion
Half-life
Receptor density (this is really important)
Receptor-hormone affinity

NOTE: We can play with receptor-hormone affinity to make synthetic hormones that bind better than the natural hormone.

Question 21

What are3 different patterns and duration of secretion?

Answer 21

Episodic
Basal
Sustained

Question 22

What is Episodic secretion?

Answer 22

Burst or pulse

NOTE: generally associated with hormones under nervous control.

Question 23

What is Basal secretion?

Answer 23

Secretion stays low, but fluctuates with low amplitude pulses.

Question 24

What is Sustained secretion?

Answer 24

Hormone remains elevated, but in a steady fashion for a long period.

NOTE: Steroids tend to be secreted this way.

Question 25

Where are steroids metabolized and excreted?

Answer 25

Metabolized: Liver Excreted: Urine and feces

Question 26

What organ is usually larger in high producing dairy cows?

Answer 26

Livers

Question 27

Why can pregnancy tests be a urine test?

Answer 27

Because the protein hormones (eg. hCG) are metabolized in the liver and excreted by the kidneys.

Question 28

What is estrus?

Answer 28

"Heat" or secual receptivity

Question 29

What is estrous?

Answer 29

Length of the estrous cycle

Question 30

What is an estrous cycle?

Answer 30

The period between one estrus and the next.

Question 31

What is anestrus?

Answer 31

Not cycling

Question 32

What does estrual mean?

Answer 32

Something related to estrus.

Question 33

What 3 species are polyestrus?

Answer 33

Cattle Swine Rodents

Question 34

What 4 species are seasonally polyestrus short-day breeders?

Answer 34

Sheep Goats Deer Elk

Question 35

What species is seasonally polyestrus long-day breeders?

Answer 35

Horses

Question 36

What 3 species are monestrus?

Answer 36

Dogs Wolves Bears

Question 37

What is the follicular phase?

Answer 37

Follicles are dominant structure

Question 38

What hormone is dominant during the follicular phase?

Answer 38

Estrogen

Question 39

What is the luteal phase?

Answer 39

Corpora lutea are dominant structure.

Question 40

What hormone is dominant during the follicular phase?

Answer 40

Progesterone

Question 41

What are the 4 stages of the estrous cycle?

Answer 41

Proestrus Estrus Metestrus Diestrus

Question 42

What 2 stages of the estrous cycle are in the follicular phase?

Answer 42

Proestrus | Estrus

Question 43

What 2 stages of the estrous cycle are in the luteal phase

Answer 43

Metestrus | Diestrus

Question 44

During what stage of the estrous cycle does estrogen secretion begin?

Answer 44

Proestrus

Question 45

During what stage of the estrous cycle does estrogen secretion peak?

Answer 45

Estrus

Question 46

During what stage of the estrous cycle does prostaglandin secretion being?

Answer 46

Metestrus

Question 47

During what stage of the estrous cycle is progesterone secretion sustained at high levels?

Answer 47

Diestrus

Question 48

Why do you need to watch progesterone levels in dogs?

Answer 48

Because they have a longer period of receptivity.

Question 49

What is important to remember about diestrus in the bithc?

Answer 49

It is always 2 months no matter what.

Question 50

What is important to remember about cats?

Answer 50

They are induced ovulators.

Question 51

What are 5 conditions that would result in anestrus?

Answer 51

``` Pregnancy Lactation Seasons Stress Pathology ```

Question 52

What are 3 factors that might cause a true anestrus?

Answer 52

Nutrition Stresses Pathology

Question 53

What are 2 causes of apparent anestrus?

Answer 53

Failure to detect estrus | Failure to know that she is pregnant

Question 54

What species are induced ovulators?

Answer 54

Llamas and Queens