A&P 2 Ch.28 Reproductive
uterine tubes
? provide nutrient rich lipids and glycogen to spermatozoa and developing pre-embryo
muscles
? relax or contract to move testes away or toward body to maintain acceptable testicular temperature
increase, decrease
GnRH pulse frequency and amplitude change over course of ovarian cycle. an increase in estrogen equals a ? in GnRH and an increase in progesterone equals a ? in GnRH
acrosomal cap
a membranous compartment that contains enzymes essential to fertilization; made of fused saccules of spermatid's golgi apparatus
seminal fluid
a mixture of secretions from seminal glands, prostate gland, and bulbo-erethral glands; discharged into ejaculatory duct at emission when peristaltic contractions are underway
meiosis
a special form of cell division involved only in production of gametes (spermatozoa & oocyte); produces 4 haploid (daughter) cells with 23 chromosomes each that are not identical
functions of male glands
activate spermatozoa; provide nutrients for motility; propel sperm and fluids along the reproductive tract through peristaltic contractions; produce buffers to counteract acidity of vagina
germ cell formation
end result is 4 spermatozoa and 1 oocyte
female arousal
parasympathetic activation leads to engorgement of erectile tissues and vaginal walls increase secretions of cervical mucous glands and greater vestibular glands; blood vessels fill; fluid moves from underlying connective tissues to vaginal surface
Mitosis
part of somatic cell division; produces 2 diploid daughter cells w/identical pairs of chromosomes
head
part of sperm that contains nucleus and chromosomes; has an acrosomal cap.
middle piece
part of sperm that contains the mitochondria in a spiral around microtubules; activity provides ATP to move the tail
female orgasm
peristaltic contractions of uterine and vaginal walls
ejaculation
powerful rhythmic contractions that push semen out. oxytocin dilates blood vessels and facilitates muscle contraction; erect penis, orgasm follows
female reproductive system
produces sex hormones and functional gametes; protects and supports developing embryo; nourishes newborn infant
inhibin
released by nurse cells in response to factors released by spermatozoa; give nurse cells feedback control of spermatogenesis by regulating FSH and GnRH (inc. inhibin, dec. GnRH, dec. FSH)
uterine cycle
responds to hormones of ovarian cycle; 3 phases include: menses, proliferative, and secretory; repeating series of changes in endometrium; lasts 21-35 days; avg. 28
12-24 hours
secondary oocyte must meet spermatozoa during the first ?
prostatic fluid
slightly acidic; forms 20-30% of semen volume; contains seminal plasmin (antibiotic); ejected into prostatic urethra
absorb
sperm must ? nutrients (fructose) from surrounding fluids
9 weeks
spermatogonial division to spermiation takes about how many weeks?
capacitation
spermatozoa become motile when mixed with secretions of seminal glands and capable of fertilization when exposed to female reproductive tract
immature, cilia, epididymis
spermatozoa detach from nurse cells and are free in the lumen of seminiferous tubule; they are physically mature, but functionally ? and incapable of locomotion or fertilization; moved by ? lining efferent ductules into the ?
mature, can't
testes produce physically ? spermatozoa that ? fertilize an oocyte
menses and proliferative
what are the two primary stages of the uterine cycle that occur during the follicular phase of the ovarian cycle?
spermatogenesis
what is the process of sperm production that involves three integrated processes: mitosis, meiosis, and spermiogenesis?
female gonads
what produces estrogen, progesterone, and testosterone?
anterior pituitary
what releases FSH and LH?
spermatogonia
(stem cells) divide by mitosis to produce 2 daughter cells; one remains as a spermatogonium and the other differentiates into primary spermatocyte; meiosis begins with this for males.
proliferative phase
2nd phase of uterine cycle; epithelial cells multiply; completely restore uterine lining; blood supply extends into new lining
secretory phase
3rd phase of uterine cycle; hormonal secretion increases; arteries of uterine wall elongate and spiral through outer lining; peaks about 12 days after ovulation; glandular activity declines; generally lasts 14 days
FSH, increase estrogen, LH, ovulation, increase progesterone, decrease progesterone
List the order of the ovarian cycle
oogenesis (ovum production), FSH, increase
begins before birth; accelerates at puberty; ends at menopause; primary oocytes remain suspended until puberty; at puberty, inc. ? leads to ? estrogen, which triggers the start of the ovarian cycle
primary spermatocyte
begins meiosis and forms secondary spermatocytes
spermiogenesis
begins with spermatids (small, unspecialized) that differentiate into mature spermatozoa and attach to cytoplasm of nurse cells; process of sperm maturation; last stage of spermatogenesis
female reproductive hormones
control female reproductive cycle; coordinate ovulation and uterus preparation; involves secretions of pituitary gland and gonads
secondary spermatocyte
differentiate into spermatids (immature gametes)
meisosi I
during fetal development between 3-7 months primary oocytes prepare for meiosis but stop at ?
progesterone
during menses, there is a decrease in which hormone?
FSH and estrogen
during the proliferative phase, there is an increase in what two hormones?
spermatid
each ? matures into one spermatozoon attached to cytoplasm of nurse cells
unevenly, secondary, fertilization
each month after, primary oocytes divide ? into 1 ovum and 2-3 polar bodies that disintegrate; ovary releases ? oocyte (not mature) suspended in metaphase of meiosis II, meiosis complete upon ?
menses
first phase of the uterine cycle; it's the degeneration of the uterine lining caused by constriction arteries reducing blood flow, oxygen, and nutrients; degenerating tissues break away, enter uterine lumen; only outer layer of uterus is affected, deeper layer is supplied by different arteries
fibrinogen
forms a temporary clot in vagina; slightly basic to neutralize acids in prostate glands and vagina; initiates first step in capacitation
zygote
fusion of male and female gametes for a total of 46 chromosomes
composition of seminal fluid
high fructose concentration and prostaglandins to stimulate smooth muscle contractions; fibrinogen
ovarian cycle
includes monthly oogenesis between puberty and menopause; after sexual maturation, different groups of primordial follicles each month; two phases: follicular (preovulatory) and luteal (postovulatory)
male stimulation
initiates secretion of bulbo-erethral glands; lubricates penile urethra and surface of glans; lead to coordinated processes of emission and ejaculation
perimenopause
interval immediately preceding menopause; ovarian and uterine cycles become irregular due to shortage of primordial follicles, estrogen levels decline, and ovulation is not triggered
male arousal
leads to increased parasympathetic outflow over pelvic nerves, leading to an erection
spermatozoa
lose contact w/seminiferous tubule and enter fluid in the lumen
functions of nurse cells
maintain blood-testis barrier; support mitosis and meiosis; support spermiogenesis; secret inhibin; secrete androgen-binding protein; secrete mullerian-inhibiting factor
andropause
male climacteric; period of declining reproductive function; circulating testosterone begins to decline between ages 50-60; sperm production continues; sexual activity gradually decreases
epididymis
monitors and adjust fluids produced by seminiferous tubules; recycles damaged spermatozoa; stores and protects spermatozoa (facilitates functional maturation)
estradiol
most abundant estrogen; most pronounced effects on target tissues; dominant hormone prior to ovulation
testosterone
most important androgen; produced around week 7, prenatal peak at 6 months; stimulates spermatogenesis; libido(CNS); metabolism (protein synthesis, RBC formation, and muscle growth); establishes 2nd sex characteristics (facial hair, body size, adipose tissue deposits); maintains accessory glands and organs of male reproductive tract; diffuses across target membrane and binds to intracellular receptor (direct)
2 degrees lower
normal sperm development in testes requires temperatures ? than body temperature
support mitosis and meiosis
nurse cells are stimulated by FSH and testosterone; stimulated nurse cells promote division of spermatogonia and meiotic divisions of spermatocytes
support spermiogenesis
nurse cells surround and enfold spermatids, provide nutrients and chemical stimuli for development, and phagocytize cytoplasm shed by developing spermatids
tail
only flagellum in the human body; whiplike organelle; moves cell from one place to another; has a complex, corkscrew motion
estrogen
stimulates bone and muscle growth; maintains 2nd sex characteristics; affects CNS activity (in hypothalamus increases sex drive), maintains accessory reproductive glands and organs; initiates repair and growth of endometrium
detumescence
subsidence of erectile tissue after ejaculation
nurse cells
support sperm production; affect mitosis, meiosis, and spermiogenesis in the seminiferous tubules
emission
sympathetic simulation, peristaltic contractions push fluid and spermatozoa along urethra; contractions in seminal and prostate gland; sympathetic contraction of urinary bladder and internal urethral sphincter prevent passage of semen into bladder
menstruation
the process of endometrial sloughing; lasts 1-7 days; sheds 35-50 mL blood
menopause
the termination of uterine cycles; ages 45-55; circulating concentrations of estrogens and progesterone decline; production of GnRH, FSH, and LH rise sharply
ejaculate
the volume of fluid produced by ejaculation; contains seminal fluid, sperm, and enzymes
decline of estrogen
this leads to reduction in uterus and breast size, thinning of urethral and vaginal epithelia, and reduction in bone depostion
semen
typical ejaculation releases 2-5 mL, 20 million-100 million sperm/mL