EXAM 6 Flashcards
list the functions of the reproductive system.
Produce, store, nourish and transport gametes (sex cells)
Describe the hormonal control of testicular and ovarian functions: HPG (hypothalamic-pituitary-gonadal axis does what?
Hypothalamus secretes what?
Gonadotropins stimulate what?
Regulates testicular or ovarian functions. HPG production of gametes (sex cells)-gametogenesis. Production of sex hormones.
Hypothalamus secretes gonadotropin-releasing hormone. GnRH. This stimulates anterior pituitary to release gonadotropins FSH and LH
Gonadotropins stimulate production of sex hormones in gonads
Describe the functions of LH, FSH, testosterone and inhibin in the male.
FSH stimulates sustenocytes in males, it keeps high levels of testosteron.
LH stimulates interstitial Leydig cells to produce testosterone. TEstosterone stimulates spermatogenesis. Testosterone acts back on hypothalamus and pituitary with negative feedback loop.
Inhibin, produced by sustenocytes, inhibits anterior pituitary (FSH only)
Describe the functions of LH, FSH, estrogen, progesterone, and inhibin in the female.
FSH stimulates granulosa cells of follicle in ovary to produce estrogen.
LH Stimulates thecal cells in ovary to produce androgens which become estrogen. LH surge causes the ovulation which causes corpus luteum development. Estrogen stimulates oogenesis and follicle development in ovary. !st rising estrogen acts back on hypothalamus and pituitary (negative feedback) . 2nd, brief positive feedback causes ovulation.
Progesterone is produced from corpus luteum to maintain uterine wall. Acts back on hypothalamus and pituitary negative feedback.
Inhibin, produced by granulosa cells, also act on anterior pituitary to inhibit FSH only.
Define puberty and discuss the changes that occur to bring about secondary sexual characteristics
Male: Testosterone causes gamete production and secondary sex characteristics(facial, pubic, and axillary hair). Bone and muscle grown, plate closure @ 18-21. Change in CNS behaviors, thickened throid cartilage, deepened voice, increased BMR.
Female puberty: Estrogen causes gamete production and secondary sex characteristics(pubic, axillary hair, bone and muscle growth, pelvis widens, epiphyseal plate closure, change in CNS behaviors, increased fat deposit in mammary glands and breast development, enlargement of reproductive organs and first menarche (menstrual period)
Describe the effects of aging on the reproductive systems and define menopause and menarche.
Menopause. ages 46-54. occurs after 1 year of no menstruation or ovulation. Hot flashes due to intense vasodilation in skin. Decline in estrogen levels>loss of bone mass.
menarche. 1st period.
Outline the events of spermatogenesis and oogenesis (gameotogenesis).
OOgenensis only:
Both start with germ cells that undergo meiosis I and II. Both also involve addtional cell development. Spermatids must develp a tail. OOYctes(eggs) must develop a complex follicle. Spermatogenesis: prduces male sperm (spermatozoa). Begins at puberty. Produces 4 sperm from each spermatogonium (stem cell). Porduction continures through lifetime.
OOgenesis: produces female egg (ovum, oocyte). Begins before female is born, maturation and ovulation at puberty. produces 2 oocyte from each oogonium (stem cell). Only maturation and ovulation continues until menopause.
Outline the events of spermatogenesis.:
Spermatogonia near seminiferous tubule wall divide by mitosis.
Type B daughter cells develop into primary spermatocytes and migrate to lumen. Primary spermatocytes undergo Meiosis I and Secondary spermatocytes undergo Meiosis II to become spermatids. Spermiogenesis (last step of spermatogenesis) spermatids become motile. DNA compacts. Cell elongates and sheds cytoplast. Forms a tail
Describe the structure of a sperm and an ovulated oocyte.
Head contains genetic material (DNA). Acrosome helmet (hat) has enzymes for egg entry. Midpiece is a metabolic (ATP move tail) and contains lots of mitochondria for cellular metabolism. Tail it the flagellum. It is for movement (locomotion).
Structure of an ovulated oocyte. Secondary oocyte surrounded by zona pellucida (thick glycoprotein layer) and corona radiata, made up of a crown of granulosa cells.
List the structures sperm pass through in order to leave the body
seminiferous tubule of the testes>rete testes> epididymis> ductus deferens> ejaculatory duct> prostatic urethra> membranous urethra> spongy urethra> external urethral orifice.
Describe the structure and function of the male reproductive organs including the testis,
testis consists of lobules which contain seminiferous tubules (contain sperm and sustenocytes) and leydig cells around seminiferous tubules produce testosterone
Male reproductive: Epididymis
epididymis (smooth muscular duct) >sperm gain ability to swim and are stored until ejaculation.
male reproductive:
Scrotum (hair, skin muscle):
allow for…
allow sperm production @ cooler temperatures. Muscles contract when body temp decreases which makes testes closer to body.
Male reproductive: Ductus deferens
and ejaculatory duct
Smooth muscular tube, peristalsis moves sperm in spermatic cord
Ejaculatory duct is form from seminal vesicle and ductus deferens
male reproductive:
Penis:
erectile organ with 3 chambers (2 cavernosa and spongiosum) erection from increased blood flow. Glans (enlarged head) contains prepuce (cuff, foreskin)…Function is to deliver sperm to female reproductive tract
Discuss the role of sustenocytes (Sertoli) cells in the blood-testis barrier.
These are nurse cells. Supportive cells provide nutrients, inhibin, testicular fluid (transports sperm). They are joined by tight junctions to form blood-testis barrier. It keeps these from being attacked before puberty. It seals inner compartment to prevent immune system from reacting
Define semen and state its composition and the function of each constituent.
All glands contribute to semen. Sperm (20-150million/ML) plus transport medium (Fluid).. so Sperm +Fluid = semen
Seminal vesicles
Prostate gland
Bulbourethral glands
locate and differentiate among the seminal vesicles, prostate gland, and bulbourethral glands
Seminal vesicles (posterior to bladder, 70%) fluid high concentration of fructose (sugar, they need energy) prostaglandins and CF.
Prostate gland: Inferior to bladder 20-30%) .>fluid that activates sperm.
Bulbourthral glands (inferior to prostate, 5%).>neutralize acid in urethra and lubricate glans penis
Describe the structure and function of the female reproductive organs including the ovaries and uterine tubes:
Ovaries are in pelvic cavity, held by several ligaments.
Uterine tubes (smooth muscle tubes) ciliated fimbriae stiffen to receive mature oocyte following ovulation from ovary. Peristalsis and beating cilia guide oocyte to uterus
female reproductive:
uterus and cervix
uterus: smooth muscular vessel. Site for implantation of fertilized oocyte, nourishment for developing fetus.
Cervix: narrowed neck of uterus
female reproductive: Vagina, Labia majora and minora
Mammary glands
Vagina (smooth muscular canal) pathway for penis/sperm, birth canal, menstrual flow. Inner mucosal membrane (stratified squamous) contains rugae (stimulate penis) is acidic due to bacterial metabolism of glycogen. Labia majora hair covered fat folds. Minora-hair free skin folds
mammary glands begin at lactation at end of pregnancy. due to oxytocin and positive feedback (letdown reflex) consists of lubules w alveoli (produce milk), ducts lead to nipple
Describe the ovarian cycle phases, and relate them to events of oogenesis.
Follicular Phase Days 1-14.Selection and development. Follicle secretes increased estrogen which causes LH sure (positive feedback). Primary oocyte completes meiosis I an becomes secondary oocyte.
Ovulation Day 14. LH causes oocyte and corona radiata release from follicle and ovary.
Days 14-28 Luteal Phase: corpus luteum produces estrogen and progesterone (10 days) then degenerates. This Phase is always 14 days long.
Signs of ovulation:
twinge of abdominal pain, inflammatory response, weakening of ovary wall
Outline the major events of each phase of the uterine menstrual cycle and correlate them with the events of the ovarian cycle
Deals with changes in uterine endometrium (lining of uterus). Uterine cycle correlates with ovarian cycle. Ovarian controlled by pituitary hormones (FSH, LH). Uterine controlled by ovarian hormones (estrogen, progesterone).
Mensis and proliferative = follicular (days 1-14).
Secretory =luteal (days 15-28). (uterine corresponds with ovarian cycle).
Menstrual phase Days 1-5 (mensis) drop in estrogen and progesterone. Sheds blood and stratum functionalis of endometrium. In ovary, maturation of next oocycte begins.
