laboratory activity fbs vi (3)

8/12/2019 Laboratory Activity Fbs Vi (3)

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BAGIAN FISIOLOGI

FK UNISBA


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Review the function of each part of Male andFemale Reproductive organ

Regulation of hormones on MaleReproductive

Regulation of hormones on FemaleReproductive

Reproductive Cycle on Female Reproductiveinclude Ovarian Cycle

Menstrual Cycle


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Male reproductive system Testes : Produce sperm and secrete the male sex

hormone testosterone

Hypothalamus Male reproductive duct : transport, store and

assist in maturation of sperm, conveys sperm tothe exterior Accessory sex glands: secrete mostof the liquid portion of semen

Penis contains the urethra : a passageway forejaculation of semen and excretion of urine

Scrotum : supporting structure for the testes


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Female reproductive system Ovaries : produce secondary oocytes and hormones,

including progesterone and estrogens (female sexhormones), inhibin and relaxin

Uterine tubes (fallopian tube) : transport a secondaryoocyte to the uterus and normally are the sites wherefertilization occurs

Uterus : site of implantation of a fertilized ovum,

development of the fetus during pregnancy, and labor Vagina : receives the penis during sexual intercourseand is a passageway for childbirth

Mammary glands : synthesize, secrete and eject milkfor nourishmentof the newborn


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Seminiferous tubules: produce sperm (spermatogenesis) Spermatogenic cells : the sperm-forming cells Starting at puberty, sperm production begins at the periphery of

the seminiferous tubule. (Students had been learnt about spermatogenesis)

Sertoli cells: supporting spermatogenesis Nourish spermatocytes, spermatids and sperm Phagocytize excess spermatid cytoplasm as development

proceeds Control movements of spermatogenic cells Release of sperm into the lumen of the seminiferous tubule Produce fluid for sperm transport Secrete androgen-binding protein and the hormone inhibin Mediate the effect of testosterone and FSH


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Leydig cells (interstitial endocrinocytes) : the cluster of cells that lie in thespace between adjacent seminiferous tubules.

Secrete testosterone (the most prevalent androgen)The functions of androgen: Promote development of masculine characteristics Promote libido (sexual desire) in both male and female ScrotumThe function of scrotum : regulate the temperature of the testes. Normal sperm production requires a temperature about 2-3oC below

core body temperature. This lowered temperature is maintained withinthe scrotum because it is outside the pelvic cavity.

The cremaster muscle elevates the testes upon exposure to cold (andduring sexual arousal). This action moves the testes closer to the pelviccavity, where they can absorb body heat. Exposure to warmth reversesthe process.

The dartos muscle also contracts in response to cold and relaxes inresponse to warmth


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Epididymis: The site where sperm matureacquire motility and the

ability to fertilize an ovum Stores sperm and helps propel sperm by peristaltic

contraction of this smooth muscle into the ductus (vas)deferens. Sperm may remain in storage in the ductusepididymis for a month or more

Ductus deferens :

Strores sperm, which can remain viable here for up toseveral months. Conveys sperm from the epididymis toward the urethra by

peristaltic contractions of the muscular coat. Sperm thatare not ejaculated are eventually reabsorb.


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Spermatic cord : A supporting structure that ascends out of the

scrotum

Ejaculatoryducts: Eject sperm and seminal vesicle secretion to the

prostatic urethra just before ejaculation

Urethra A passageway for both semen and urine Prostatic urethra Membranous urethra Spongy (penile) urethra


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Seminal vesicle: Secrete: alkaline, viscous fluid (60% semen

volume) containing fructose, prostaglandins,

clotting proteins. Alkaline to neutralize the acidic environment. Fructose for ATP production of the sperm. Prostaglandin for sperm motility and viability,

stimulate smooth muscle contraction withinfemale.

Clotting proteins for semen coagulation afterejaculation.


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Prostate: Secrete: milky, slightly acidic fluid (25 % semen volume ) Citric acid for ATP production. Proteolytic enzymes: prostate-specific antigen (PSA), pepsinogen,

lysozyme, amylase, hyaluroindase (breakdown the clottingproteins from the seminal vesicles).

Acid phosphatase: function unknown. Seminalplasmin: antibiotic.

Bulbourethral gland: Secrete: alkaline fluid, mucus Alkaline fluid: protect the sperm by neutralizing acids from urine. Mucus: lubricates the end of the penis, lining the urethra

decrease the number of sperm damaged during ejaculation.


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At puberty secretion of GnRH is increased, GnRH stimulates FSH and LH, LH stimulates Leydig cells (interstitial cells) to secrete testosterone. In the external genitals and prostate, testosterone is converted to

dihydrotestosterone (DHT) by 5-alpha reductase.

FSH indirectly stimulate spermatogenesis. FSH and testosterone stimulate secretion of androgen-binding protein

by Sertoli cells. Release of FSH is stimulated by GnRH and inhibited by inhibin. Relase of LH is stimulated by GnRH and inhibited by testosterone.

Effects of Testosterone and DHT:- Male pattern of development (before birth),- Enlargement of male sex organs and expression of male secondary sex

characteristics (starting at puberty),- Anabolism (protein synthesis).


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Progesterone is secreted mainly by the corpus luteum Cooperates with estrogen to prepare and maintain

the endometrium for implantation of a fertilizedovum and to prepare the mammary glands for milk

secretion. High levels of progesterone also inhibit secretion of

GnRH and LH. Inhibin is secreted by granullosa cells of growing

follicles and by the corpus luteum after ovulation. Inhibit secretion of FSH and to a lesser extent, LH.


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Relaxin is secreted by corpus luteum (smallquantity)to relaxes the uterus by inhibitingcontractions of the myometrium.

During pregnancy, the placenta produces muchmore relaxin, and it continues to relax uterinesmooth muscle.

At the end of pregnancy, relaxin also increases

the flexibility of the pubic symphysis and mayhelp dilate the uterine cervix, both of which easedelivery of the baby.


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Terms related to Female Reproductive Cycle Ovarian cycle: a series of events in the ovaries

that occur during and after the maturation of an

oocyte. Uterine (menstrual) cycle: a concurrent series of

changes in the endometrium of the uterus forreceiving the fertilized ovum.

Female reproductive cycle: encompass theovarian and uterine cycles, hormonal changes,related cyclical changes in the breast and cervix


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Hormonal Regulation GnRH stimulates FSH and LH. FSH initiates follicular growth, LH stimulates further

development of the ovarian follicles. LH stimulates the theca cells to produce androgens. FSH influence androgens uptake by the granulosa

cells to be converted into estrogens. At midcycle: LH triggers ovulation, promotes

formation of the corpus luteum. Corpus luteum produces and secretes estrogens,

progesterone, relaxin and inhibin.


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Phases of the Female Reproductive Cycle Menstrual Phase (Menstruation, Menses) Pre-ovulatory Phase (Proliferation Phase)

Menstruation and Proliferation Phase= Follicular phase. Ovulation Post-ovulatory Phase (Secretory Phase)


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Terms related to Female Reproductive Cycle Ovarian cycle: a series of events in the ovaries

that occur during and after the maturation of an

oocyte. Uterine (menstrual) cycle: a concurrent series of

changes in the endometrium of the uterus forreceiving the fertilized ovum.

Female reproductive cycle: encompass theovarian and uterine cycles, hormonal changes,related cyclical changes in the breast and cervix


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Hormonal Regulation GnRH stimulates FSH and LH. FSH initiates follicular growth, LH stimulates further

development of the ovarian follicles. LH stimulates the theca cells to produce androgens. FSH influence androgens uptake by the granulosa

cells to be converted into estrogens. At midcycle: LH triggers ovulation, promotes

formation of the corpus luteum. Corpus luteum produces and secretes estrogens,

progesterone, relaxin and inhibin.


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laboratory activity fbs vi (3)

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