10A: Hormonal control of reproduction (copy)

Vertebrate reproduction

Cyclic activity (changing seasons)

Case of ewes (female sheeps)

Reproductive cycle that last for 15-17 days

Cycle starts at the end of the summer (september to october) then ends in winter

February-March

If the female sheeps mated in october, birth will be during what months? (Considering optimal environment for offsprings)

Pelagic worms

Reproductive process governed by lunar cycles

October to November

At what month do the pelagic worms break their tails engorged with gametes, filling up the ocean surface

FSH and LH

Hormones in Testes or ovaries

TSH

Hormone in thyroid

ACTH

Hormone in adrenal cortex

Prolactin

Hormone in mammary glands

MSH

Hormone in Melanocytes

Endorphin

Hormone in pain receptors in the brain

Growth hormone

Hormone in liver and bones

Hypothalamus

contains neurosecretory cells that secretes gonadotropin-releasing hormone

Follicle-stimulating hormone and Luteinizing hormone

Via portal vessels, the GnRH gets transported into pituitary gland where it stimulates the release of gonadotropins:

Follicle-stimulating hormone and Luteinizing hormone

Act on the gonads to secrete their own hormones

Estrous cycle

Cycle reproductive patterns of mammals with lower vertebrates

Menstrual cycle

Cycle reproductive patterns of mammals with anthropoid primates

Estrous cycle

Associated with more pronounced behavioral cycles than are menstrual cycles

Estrus

Period of sexual activity- also known as heat

Estrus

The only time the condition of vagina permits mating

Proestrus

Period of preparation (follicles grow)

Metestrus

Period of repair

Diesterus

Uterus becomes normal, small and anemic

Monoestrous

Single estrous cycle in a breeding season

Monoestrous

Frequency of estrous cycle in dogs and foxes

Polyestrous

Recurrence of estrous cycle in breeding season

Polyestrous

Frequency of estrous cycle in mice, rabbits, and squirrels

Menstrual cycle

Refers specifically to the changes that occur in the uterus (uterine cycle)

Menstrual cycle

Caused by cyclic events in the ovaries (ovarian cycle)

Estrogen

Ovaries produce

Testosterone

Testes produce

GnRH

During hormonal control in males, the Hypothalamus synthesizes and releases

FSH

Acts on the Sertoli cells of the testis to support the maturation of sperm

Sertoli cells

One of the function of ___________ in response to FSH is to secrete androgen-binding proteins that bind to testosterone from the interstitial cells, crossing the seminiferous tubules

Androgen-binding proteins

Because of the _________, the residency period of testosterone is prolonged and maintained for sperm maturation

Inhibin

FSH is regulated by ___________ produced by sertoli cells

Testosterone

LH acts on Leydig cells to produce _________

Negative feedback

FSH, LH, GnRH are regulated vi

Testosterone

Supporting maturation of sperm in spermatogenesis

Testosterone

Incubates the development of primary and secondary sex characteristics

Primary sex characteristics

Organs and accessory organs of the reproductive system

Secondary sex characteristics

Physical and behavioral characteristics

Theca cells

What cells acts on LH

Granulosa cells

What cells acts on FSH

Androgens

Produced by theca cells that can cause the membrana granulosa in the developing follicle and are converted into estrogen or estradiole

Enzyme aromatase

Androgens are converted into estrogen or estradiol via

Estrogen

Granulosa cells, in response to FSH, secrete additional _______

Inhibin

Secretary factor released by Granulosa cells

Ovarian cycle and uterine cycle

Two phases of the reproductive cycle in human females

Menstrual cycle

Cycle involving changes in the endometrium of the uterus

Ovarian cycle

Cycle involving histological changes in the ovaries

28 days

The length of the menstrual cycle on average

14th day

Ovulation, the release of the mature oocyte, occurs on the middle of the cycle or the _____________

Follicular phase and Luteal phase

Two phases of the ovarian cycle

Follicular phase

Occurs from day 1 until the middle or day 14 of the cycle

Luteal phase

Occurs from day 15 to the end or day 28 of the cycle

Follicular phase

In the gonadotropic hormones, FSH and LH are released during the _____________

Estrogen levels

Towards the middle of the cycle, there is a steep increase in ___________ as a result of follicular growth. This mark sends a positive feedback regulation to the hypothalamus and pituitry gland

T

T/F: High level of estrogen stimulates the release of FSH and LH

T

T/F: LH has a steeper increase than FSH

LH

Hormone of ovultion

LH and estrogen

The steep increase of ____________ causes the mature follicle to burst

Antral fluid

After ovulation, the surrounding granulosa and theca cells then collapse as the _________ is released with the oocyte.

Corpus luteum

yellow and bloody collapsed cell known as the

Corpus luteum

The Luteal phase is when the _________ forms.

Progesterone

hormone that supports gestation and maintains the uterine lining

Luteal phase

Progesterone is at its peak during the

Progesterone and Estrogen

As the Corpus Luteum degenerates, there is a decline in the production of _____________ at the end of the Luteal Phase.

Menstrual and Proliferative phases

first two phases of the Uterine Cycle which correspond with the Follicular Phase of the Ovarian Cycle.

Estrogen

Increasing levels of ________ coincide with the preparation of the uterine lining for future embryonic development - proliferation of endometrial cells + blood vessels and endocrine glands.

Secretory phase

Third phase of uterine cycle that corresponds with the luteal phase

Secretory phase

Progesterone level (followed by Estrogen level) peaks during the ______________. This phase corresponds with the luteal phase of the ovarian cycle

Progesterone and estrogen

responsible for maintaining the integrity and thickness of the endometrial / uterine lining

Secretory phase

The endometrial/uterine lining is thickest at this point

Menstrual flow

IF the ovulated oocyte is NOT fertilized, it will undergo degeneration. With the decline in Progesterone and Estrogen, the uterine lining will no longer be maintained—blood vessels burst, uterine lining + glands degenerate—resulting in the

Secretory phase

Among the three phases in the uterine cycle, this phase is the most stable.

14 days

The secretory phase typically lasts for how many days?

14

If the menstrual cycle length occurs for 28 days cycle, it will ovulate on day ___

25-30 days

Most cycle typically lasts for

F

Younger women have shorter cycles than older women

30 days

Menstrual cycle of 15-19 y/o

30 days

Menstrual cycle of 30 y/o

28 days

Menstrual cycle of 35 y/o

FSH

Stimulates the growth + development of the follicle

FSH

Stimulates estrogen secretion

Enhances the effect of LH in stimulating ovulation

LH

Stimulates the final development of the follicle

LH

Stimulates ovulation

Estrogen

Stimulates the repair of uterine liningh

Inhibits

At high concentration of estrogen, it _____ (inhibits/stimulates) FSH

Stimulates

During pituitary hormone surge, estrogen _______ (inhibits/stimulates) further FSH production

Stimulates

As conc. peaks in estrogen, ___________ (inhibits/stimulates) the release of LH

Progesterone

maintains uterine lining

Inhibits

Progesterone __________ (inhibits/stimulates) release of FSH and LH

< 24

Normal limits of frequent frequency of menses

24-39

Normal limits of normal frequency of menses

>38

Normal limits of infrequent frequency of menses

>8.0

Normal limits of prolonged duration of flow

4.5-8.0

Normal limits of normal duration of flow

<4.5

Normal limits of shortened duration of flow

>80

Normal limits of heavy volume of monthly blood loss