organs responsible for producing sperm and reproductive hormones
Testes
accessory sex glands that produce components of semen
Seminal glands
Prostate
Bulbo-urethral glands
system of ducts that sperm is delivered through to the exterior
pathway of sperm
Seminiferous tubules --> straight tubule--> rete testis-->
efferent ductules--> epididymis--> ductus deferens-->
ejaculatory duct-->urethra
area of sperm production
Seminiferous tubules
decrease viscosity of mucus in cervix
stimulates reverse peristalsis in uterus
Prostaglandins
hormones that leads to sperm motility
hormone relaxin and other enzymes
contains fructose for ATP production
protects and activates sperm
facilitates sperm movement
suppresses female immune response
antibacterial action
semen
produce viscous alkaline seminal fluid
fructose, citric acid, coagulating enzyme, and prostaglandins
70% of volume of semen
Seminal glands (vesicles)
Produce thick, clean mucus
Bulbo-urethral glands
secretes milky, slightly acidic fluid that contains citrate, enzymes,
and prostates specific antigens (PSA) and plays a role in sperm activation
enters prostatic urethra during ejaculation
1/3 of semen volume
Prostate gland
cell division produing haploid daughter cells (gametes)
Meiosis
cell division that produces clones/copies
mitosis
functions of meiosis
half number of chromosomes
introduce genetic diversity
effect of crossing over
Variability of gametes
reduction division of meiosis to form haploid cells
reduce chromosome number
Meiosis I
Prophase I events unique to meiosis I
Synapsis
Crossing over
Homologous chromosomes pair forming tetrad of four chromosomes
Synapsis
exchange of genetic material between male and female chromatid that
create unique chromosomes and, therefore, unique siblings
Crossing over (chiasmata)
Things a daughter cell has at the end of Meiosis I
Two copies of either maternal or paternal chromosome
Haploid chromosome numbers but each chromosome has twice the normal
amount of DNA
Equational division of meiosis
like mitosis except no chromosome replication before it begins
Meiosis II
Spermatids become spermatozoa (sperm)
spermiogenesis
large support cells that extend through wall of tubule and surround
developing cells
provide nutrients and signals to dividing cells
produce chemical mediators to regulate spermatogenesis
Secrete testicular fluid into lumen for sperm transport
Sertoli cells
roles of sustenocytes
Large supporting cell
tight junctions form blood testis barrier
Prevents sperm antigens from escaping into blood, which would lead to
activation of immune system because sperm isn't recognized as self
Blood testis barrier
functional area of sperm containing the nucleus and acrosome
Head
Organelle similar to lysosomes that contains hydrolytic enzymes that
enable sperm to penetrate egg
Acrosome
functional area of sperm that contains mitochondria for ATP
production that moves tail
Midpiece
locator region of sperm that consists of flagellum
Tail
hormone released by hypothalamus that stimulates the anterior
pituitary gonadotroph cells to secrete FSH and LH
Gonadotropin-releasing hormones (GnRH)
secreted by anterior pituitary gonadotroph cells
causes testicular sustenocyte to release ABP
Follicle stimulating hormone (FSH)
protein released by testicular sustenocytes that accumulates near
spermotogenic cells
Androgen binding proteins
hormone secreted by anterior pituitary gonadotroph cells that
stimulates testicular interstitial endocrine cells to produce testosterone
Leutinizing hormone (LH)
features induced in nonreproductive organs by androgens (mostly testosterene)
Male secondary sex characteristics
What are the secondary sex characteristics of males?
appearance of pubic, axillary, and facial hair
enhanced growth of chest hair
deepening of voice
skin thickens and becomes oily
bones grow, and increase in density
Basal metabolic rate increases
Basis of sex drive in males
androgen related medical conditions
Male pattern baldness
Prostate diseases
BPA
Prostate cancer
enlargement of prostate gland
common in men over 60
Benign Prostatic hyperplasia (BPA)
synthesized from cholesterol
transformed to exert its effects on some target cells
prompts spermatogenesis
targets all accessory organs
has multiple anabolic effects throughout body
Testosterone
Targets of testosterone
DHT in prostate
Estradiol in some neurons in brain
most commonly diagnosed cancer in men
treated by surgery or drugs that block DHT production
Prostate cancer
Testosterone levels in men and women
Men: 650
Women: 40
Dihydrotestosterone levels in men and women
Men: 45
Women: 20
Estradiol levels in men and women
Men: 3
Women: 6-50
Estrone levels in men and women
Men: 2.5
Women: 5-20
types of estrogens
estrone and estridiol
hypothalamus releases GnRH GnRH stimulates anterior
pituitary gonadotroph cells to secrete FSH and LH FSH
causes testicular sustenocytes to release ABP LH stimulates
testicular interstitial endocrine cells to produce testosterone
testosterone stimulates spermotogenesis negative
feedback of rising testosterone levels in anterior pituitary and
hypothalamus when sperm count is sufficient, inhibin goes
from testes to hypothalamus and pituitary to reduce GnRH and FSH
production
hormonal regulation of testicular function
production of female gametes
oogenesis
develop in primordial follicle and begin meiosis , but stall in
Prophase I
few are activated each month after puberty
Primary Oocytes
result of meiosis I
Large cell with almost all of cytoplasm and organelles of original cells
arrest in metaphase II
deteriorate if not fertilized
Secondary Oocytes
small cell that can't be fertilized
Polar body
period of follicle growth (days 1-14)
follicular phase
period of corpus luteum activity (days 14-28)
ruptured follicle collapses, antrum fills with clotted blood
lutual phase
fluid that forms during follicular phase that expands to isolate
oocyte with corona radiata stalk
Antrum
ovary wall ruptures, expels secondary oocyte with its corona radiata
to peritoneal cavity and then to fallopian tubes
ovulation
results from the fertilization of the 1-2% of ovulations that release
more than one secondary oocytes
Fraternal twins
results when one fertilized oocyte separates into two individual
daughter cells
identical twins
GnRH--> release of FSH and LH FSH and LH -->
growth of several follicles and hormone release increase
plasma estrogen levels inhibit release of FSH and LH when
estrogen levels are high, brief positive feedback on brain and
anterior pituitary stored LH, and some FSh, suddenly
released by anterior pituitary at midcycle--> surge triggers
ovulation--> primary oocyte to complete meiosis I--> secondary
oocyte--> Meiosis II negative feedback inhibits LH and
FSH release and inhibin enhances effect. Declining LH ends luteal
activity, inhibits follicle development
hormonal interactions during a 28 day ovarian cycle
uterine wall layers
perimetrium
myometriu
endometrium
parts of the endometrium
stratum functionalis
Stratum basalis
serous layer (visceral peritonium)
perimetrium
interlacing layers of smooth muscle that contracts during childbirth
myometrium
mucosal lining that consists of stratum functionalis and stratum basalis
endometrium
layer of endometrium that changes in response to ovarian hormone cycles
shed during menstruation
Stratum functionalis
layer of endometrium that forms new functionalis after menustration
unresponsive to ovarian hormones
stratum basalis
three phases of the uterine cycle
menstrual phase proliferative phase secretory
phase
the functional layer of endometrium is shed
occurs before ovulation
correspond to follicular phase
menstrual phase
the functional layer of endometrium is rebuilt
occurs before ovulation
correspond to follicular phase
proliferative phase
begins immediately after ovulation. enrichment of the blood supply
and glandular secretion of nutrients to prepare endometrium to receive
an embryo
corresponds to time of luteal phase
secretory phase
physiologial functions of estrogens
promote oogenesis and follicle growth in ovary
exert anabolic effects on female reproductive tract
support rapid but short lived spurt at puberty
induce secondary sex characteristics
metabolic effects
secondary sex characteristics of females
growth of breasts
increased deposits of subcutaneous fats
widening of pelvis
physiological functions of progesterone
works with estrogen to establish and regulate uterine cycle
promotes changes in cervical mucus
effects on placenta
inhibits uterine motility
maintain low total blood cholesterol and high HDL levels
role of high estrogens in increasing GnRH, LH, and initiating ovulation
high levels of estrogens from almost mature follicle stimulate
release of more GnRH and LH GnRH promotes release of FSH
and more LH LH surge brings about stimulation