Ovulation

Question 1

Stigma (as related to ovulation)

Answer 1

-Small protrusion at the apex of a follicle
-Represents a site of deterioration of the follicular wall prior to ovulation.

Question 2

Hyperemia

Answer 2

7-fold increase in blood flow at ovary

Question 3

Luteinization

Answer 3

Transformation of follicular cells into luteal tissue

Question 4

Hypertrophy

Answer 4

Increase in volume

Question 5

Hyperplasia

Answer 5

Increase in number

Question 6

Luteolysis

Answer 6

The process whereby luteal tissue undergoes regression and cell death

Question 7

Know how the secretion of LH are regulated.

Answer 7

-Follicle produces estradiol
-Positive feedback to produce GnRH: Surge center

Question 8

Know how the secretion of FSH are regulated.

Answer 8

-Follicle produces inhibin and estradiol both decrease the amount of FSH produced

Question 9

Know how follicle development changes with LH and FSH concentrations: Metestrus

Answer 9

Rising progesterone and stimulates small secretions of FSH

Question 10

Know how follicle development changes with LH and FSH concentrations: Diestrus Recruitment

Answer 10

-FSH stimulates recruitment of follicles: Growth of a cohort
-The growing cohort of follicles secrete estradiol
-Estradiol inhibits FSH and stimulates LH

Question 11

Know how follicle development changes with LH and FSH concentrations: Diestrus

Answer 11

-A small selection of follicles develop LH receptors on their granulosa cells
-LH encourages follicle growth and maturation (follicles produce more estradiol as they grow)

Question 12

Know how follicle development changes with LH and FSH concentrations: Diestrus

Answer 12

-One/two cells claim dominance despite the inhibition of FSH
-A LH surge sets off multiple events shortly before ovulation

Question 13

Be able to describe/explain the Deterministic model of LH surge

Answer 13

-increased GnRH secretion: required to induce the preovulatory LH surge and thus ovulation.
-Farm Species

Question 14

Be able to describe/explain the Permissive model of LH surge

Answer 14

-GnRH secretion does not increase: Preovulatory LH surge results from enhanced sensitivity of the pituitary gland to GnRH.
-Humans and Primates

Question 15

Induced Ovulation

Answer 15

-Reflex
-Rabbits, cats
-Copulation is needed for ovulation:
~Intromission stimulates the surge of LH ovulation
~Ovulation occurs through the neuroendocrine reflex

Question 16

Spontaneous Ovulation

Answer 16

-Farm animals and Humans
-Copulation or presence of male is not necessary for ovulation to occur
~Controlled by events of estrous or menstrual cycle and not affected by intromission
~Occurs due to endogenous endocrine and neuroendocrine factors

Question 17

Be able to describe the stimulus and reflex reaction that results in induced ovulation

Answer 17

-Ovulation is stimulated by the neuroendocrine reflex
-Copulation activates a reflex inducing ovulation
-Rabbits, Cat, Ferret, and Mink

Question 18

Describe the characteristics of large luteal cells luteal cells.

Answer 18

-20-70 micrometers
-Majority of progesterone synthesis/secretion
-Rarely multiply after ovulation
-Increase in volume (3-fold): hypertrophy
-Contain LH receptors: Does NOT respond to LH by increasing progesterone production (Progesterone production DOES NOT INCREASE)
-Formed from granulosa cells

Question 19

Describe the characteristics of small luteal cells.

Answer 19

-Less than 20 micrometers
-Produce some progesterone
-Increase in number: Hyperplasia (5-fold)
-Contain LH receptors: Respond to LH by increasing progesterone production
-Formed from theca interna

Question 20

Know which factors are thought to affect the “vigor” of the CL.

Answer 20

Number of cells and vascularization.