Chapter 27- Reproductive System Flashcards
function of reproductive system
- produce some reproductive hormones
- produce gametes
- facilitate fertilization
- provide nutrients and gestate fetus
- provide nutrients for newborn
functions of male reproductive system
- produce and maintain gametes
- transport gametes into female for fertilization
- secrete sex hormones
testes
- suspended by a spermatic cord within scrotum
- -produce sperm
- -produce male sex hormones
- –adrogens such as testosterone
actions of testosterone
- fetal development
- -stimulate formation of reproductive organs
- -stimulate descents of testis
- puberty
- -stimulate development of secondary sex characteristics
- -increase cellular metabolism
- -increase production of RBC
- -stimulate sexual activity
scrotum
- pouch of skin inferior to perineum
- each testis occupies a scrotal cavity
- tunica vaginalis: serous membrane surrounding each testis
- dartos muscle: wrinkling of scrotum
- cremaster mucles
- -elevation of testes closer to body
- -keeps them at a lower temperature
spermatic cord
vessels extend through inguinal canal
- ductus deferens
- gentiofemoral nerve
- differential artery
- testicular artery
- pampiniform veins
histology of testes
- lobules
- -compartments housing seminiferous tubules
- -separated from one another by the tunica albuginea
lobules cont. (more detailed)
- 800 coiled tubes
- each straightens into a straight tubule
- straight tubules meets a maze called the rete testis
- interstitial cells
- -in between the tubules
- -produce testosterone
spermatogenesis
- the process where sperm cells are made
- -occurs in the seminiferous tubules
- -meiosis occurs midway through this process
- –results in haploid sperm
spermatogenesis: nurse cells
- stimulated by FSH and testosterone
- support the growth of sperm
- maintain blood testes barrier
- produce the hormone inhibin
- -represses FSH
spermatogenesis: stages
- spermatogonia
- primary spermatocyte
- secondary spermatocyte
- spermatid
- spermatozoa
structure of a sperm
- head
- -acrosome: vesicular compartment containing enzymes to penetrate oocyte
- neck
- middlepiece: many mitochondria
- tail: a flagella
epididymis
- lies on posterior boarder of testes
- has a:
- -head
- -body
- -tail
epididymis: functions
- spermatozoa go from testes directly to epididymis
- recycles damaged spermatozoa
- stores spermatozoa and matures them (takes about 2 weeks)
ductus deferens
- aka vas deferens
- moves out of scrotum and around bladder posterior
- enlarges at the base
- -ampulla
- -peristalsis may occur
- merges with the seminal vesicles
- -becomes an ejaculatory duct
seminal vesicles
- first of three glands that contribute to semen
- posterior to bladder
- secretion:
- -60% of semen volume
- -fructose
- -prostoglandins
- -clotting factors
- causes sperm to become motile
prostate gland
- muscular, rounded organ, 4 cm diameter
- inferior to bladder
- surrounds urethra
- secretion
- -antibiotic
- -seminalplasmin
bulbourethral
- found in the urogenital diaphragm
- secretion
- -thick, alkaline mucus
penis: erectile tissue
- made of two sets of erectile tissue:
1. corpora cavernosa: two cylindrical masses with a central artery
2. corpus spongiosum: one mass that houses the urethra - both tissues fill with blood to achieve erection due to parasympathetic stimulation
penis: regions
- root: corpora cavernosa that extends to the ischial rami
- body:
- -tubular
- -consist of all erectile tissues
- glans:
- -enlarged, distal portion of corpus spongiosum
- -covered by flap of skin
urethra: three parts (male)
- prostatic urethra
- runs through prostate - membranous urethra
- through urogenital diaphragm - spongy urethra
- through corpus spongiosum
- exit at external urethral orifice
female system: functions
- produce and maintain sex cells
- transport sex cells to site of fertilization
- provide favorable environment for developing offspring
- move offspring to outside
- produce female sex hormones
ligaments
keep the system in place
- broad ligament: endoses superior internal structures
- ovarian ligament: ovary to uretus
- suspensory ligament: ovary to pelvic wall
- uterosacral ligament: inferior uterus to sacrum
ovaries
- paired organs at the lateral walls of pelvic cavity
- receive blood from ovarian arteries and veins
- covered by:
- -germinal epithelium
- -tunica albiginea
- house the gametes
Oogenesis
egg development occurs throughout a females life
- oogonium: develops before birth
- primary oocyte: develops just before ovulation
- ovum: occurs only during fertilization
ovarian cycle (early follicle development)
- all follicles start as small primordial follicles
- during the ovarian cycle, one of these will develop into a primary follicle
- -grows granulosa cells
- -starts to produce estrogens
ovarian cycle cont. (later follicle development
- primary follicle enlarges and matures into a mature follicle
- -primary oocyte becomes a secondary oocyte
- -granulosa cells increase in number
- -a fluid filled antrum forms
- -making even more estrogen
ovarian cycle: ovulation
- ovulation occurs
- -secondary oocyte is released
- the remaining follicle now develops into a corpus luteum
- -makes both progesterone and estrogen
ovarian cycles: corpus albicana
- if fertilization occurs, the corpus luteum remains
- -continue to produce progesterone and estrogen
- if not, it will deteriorate into the corpus albicans (a knot of connective tissue), and eventually disappears
- -hormone levels drop
- -cycle begins again
uterine tubes: regions
- infundibulium:
- -expanded end
- -fimbriae: finger like extensions
- ampulla
- -intermediate portion
- isthmus
- -narrow section
uterine tubes: general
- consist of smooth muscle and ciliated epithelium
- cilia beat when ovulation occurs
- oocyte has a 3-4 day trip
- -fertilization must occur during the first half of this trip
uterus
- small and pear shaped
- sits on top of the bladder
- most women have it anteflexed
- -20% have retoflexed
uterus: major sections
- fundus
- body
- -uterine cavity
- cervix:
- -internal os
- -cervical canal
- -external os
uterine wall
- perimetrium: incomplete outer visceral peritoneum
- myometrium:
- -muscular layer
- -1.5 cm thick
- endometrium
uterine wall: edometrium
- glandular inner layer
- -functional layer
- -basilar layer
- functional layer is shed and the basil layer survives during menses
uterine cycle phases
- menses
- proliferative
- secretory
menses phase
- caused by a drop in estrogen and progesterone due to the corpus albicans
- arteries constrict
- secretory tissues and glands begin to die
- functional layer is sloughed off
proliferative phase
- caused by the production of estrogen by the follicle
- basal epithelium multiplies
- glands regrow
- lasts until ovulation
uterine cycle: secretory phase
- caused by progesterone and estrogen released by the corpus luteum
- endometrial glands enlarge
- arterial elongation
- peaks at 12 days after ovulation
- -will persist with pregnancy
- -will deteriorate when corpus albicans occurs
vagina: composition
- stratified squamous epithelium, smooth muscles, elastic fibers
- rugae
- cervix projects into the vaginal canal
- exits to the outside
- -hymen: an epithelial fold that partially blocks the entrance
vagina: function
- passageway for the elimination of menstual fluids
- receive penis and hold spermatozoa
- lower portion of the birth canal
female external organs: vulva and labia minora
- vulva: the external genital area
- labia minora
- -smooth, hairless, skin flaps surrounding the vestibule, which contains the
1. uretral opening
2. vaginal entrance
female external organs: clitoris
- erectile tissue
- surrounded by a prepuce
- the outer vulva is made up the the fleshy mons pubis and labia majora
mammary glands: locaiton
- found within pectoral fat pads in the subcutaneous tissue
- supported by suspensory ligaments
mammary glands: lobes
- produce milk
- milk moves through lactiferous ducts and is stored in lactiferous sinuses
mammary glands: exit
- milk exits through nipple
- -surrounded by areola
hormones that trigger milk production
- PRL, GH, and human placental lactogen (HGL) cause milk production
- oxytocin stimulates smooth muscle contraction and ejection
development of mammary glands
- children: male and female are similar
- puberty:
- -male glands fail to develop
- -females develop due to ovarian hormones
- –alveolar glands and ducts enlarge
- –fat deposited