27) Reproductive System Flashcards
1-14 male quiz, 15-24 female quiz, 25-87 lecture notes
cell type that secretes androgens (testosterone) in the testes
interstitial cells
tube that sperm travels when leaving the epidiymus
ductus (vas) deferens
gland that produces contents that activate sperm
prostate
largest erectile tissue in the penis
corpus cavernosum
glands that create spermatozoa
testes
gland that produce much of what makes up semen
seminal vesicles
hormone that guides spermatogenesis and also secondary sex characteristics in males
testosterone
structure that guides testicular descent
gubernaculum
structure that passes through the inguinal canal
spermatic cord
cell type that regulates spermatogenesis in the testes
sustentacular cells
hormones released from the anterior pituitary gland that target the testes
LH and FSH
location inside the testes where sperm cells are produced
seminiferous tubules
structure that helps cool testes by cooling warm arterial blood
pampiniform plexus
glands that secrete a substance to clear the urethra prior to ejaculation
bulbourethral glands
reproductive female structure
ovary
structure formed after degradation of the corpus luteum
corpus albicans
takes place halfway through the menstrual cycle
ovulation
hormone that causes ovulation
LH
structure ovulated in the human female
secondary oocyte
major hormone of the secretory phase secreted by the corpus luteum
progesterone
structure in the female similar to the glands penis of the male
clitoris
major hormone of the follicular phase that guides folliculogenesis
FSH
major hormone of the proliferative phase that signals uterine development and also secondary sex characteristics
estrogen
opening to the uterus
cervix
male sex cell
sperm
*1 set of genetic instructions found on 23 chromosomes
female sex cell
oocytes (egg)
*1 set of genetic instructions found on 23 chormosomes
meiosis
*special type of division of sex cells
*two successive divisions: Meiosis I & Meiosis II
*prior to meiosis each chromosome replicates & contains 2 DNA strands (chromatids connected by centromere)
*results in genetic variability because of random alignment of chromosomes in metaphase I
first meiotic division
*separates pairs of chromosomes
*4 phases of Meiosis1: 1)prophase I, 2) metaphase I, 3) Anaphase I, 4) Telophase I
diploid cells
containing 2 sets of chromosomes in 23 pairs
haploid cells
containing 1 set of chromosomes
prophase I
homologous pairs of chromosomes lineup (synapsis), crossing over occurs
metaphase I
homologous pairs align along the equator of the cell
anaphase I
homologous chromosomes seperate, pulling to opposite poles by spindle fibers
telophase I
daughter cells have one chromosome from each homologous pair
second meiotic division
*meiosis II begins afte telophase I
*4 phases of meiosis II: 1)prophase II, 2)metaphase II, 3)anaphase II, 4) telophase II 5) results in 4 Daughter cells
prophase II
cells have one chromosome from each homologous pair
metaphase II
chromosomes align at the equator of the cell
anaphase II
daughter chromosomes move towards the poles
telophase II
spindle disappears, nuclei form, cytokinesis takes place
male reproductive system
*produces, maintains, stores, & transports sperm cells
*produces male sex hormones
*primary male sex organ: testes
*accessory male sex organ: internal & external reproductive organ
descent of testes
*testis originate near level of developing kidneys
*1-2months before birth, testosterone triggers descent into scrotum
*gubernaculum guides descent of the testes into the lower abdominal cavity, thru inguinal canal
*spermatic cord contains the ducuts deferens, blood vessels and nerves
structure of the testes
*composed of lobules seperated by connective tissue, filled with one of four seminiferous tubules
*seminiferous tubules unite to form rete testis
*rete testis joins the tubules to the epididymis
*epididymis becomes the ductus (vas) deferens
formation of sperm cells
*sustentacular cells support & nourish spermatogenic cells
*spermatogenic cells give rise to spermatogonia
*spermatogonia starts sperm cell production (spermatogenesis)
*produces 4 sperm cells from each primary spermatocyte
structure of sperm cell
*tiny tadpole-like structure
*head: contains nucleus with 23 chromosomes
*midpiece: contains many mitochondria
*tail (flagellum): propels the cell forward to the egg
male internal accessory organs
epididymides, ducuts deferntia, seminal vesicles, prostate gland, bulbourethral glands, semen
epididymides
*tightly coiled tube of the outisde of the testis
*leads to ductus deferens
*stores & nourishes immature, non-motile sperm cells, promotes their maturity
ductus deferentia
*muscular tube, leads from epididymis to urethra
*passes thru inguinal canal, enters abdominal cavity into pelvic cavity, ends behind the urinary bladder
*fuses with seminal vesicle duct, forms ejaculatory duct
seminal vesicles
*saclike structure attached to ductus deferens
*secretes alkaline fluid containing nutrients (fructose) & prostaglandin, stimulate muscle contractions in female reproductive tract
*added to sperm cells entering ejaculatory duct and greatly increases volume of fluid dishcharged
prostate gland
*surrounds urethra, below urinary bladder
*secretes a thin, milky fluid, enhancing motility of sperm cells & neutralizes acidic secretions of vagina
bulbourethral gland
*two small structures inferior to the prostate gland
*secrete fluid that lubricates the penis in preparation of intercourse
semen
*composed of sperm cells & secretions of seminal vesicle, prostate gland, & bulbourethral glands
male external reproductive organs
scrotum & peins
scrotum
*pouch of skin & subcutaneous tissue, encloses testes
*dartos muscle in scrotal wall causes skin of scrotum to hold close to testes or hang loosely (helping regulate temperature for sperm survival)
penis
*transports urine and semen
*becomes erect for insertion into vagina
*2 columns of dorsal erectile tissue: corpora cavernosa & corpus spongiosum
*root of penis attached to pelvic arch & membrane of perineum
*glans penis is distal enlargement of spongiosum
*prepuce is covering of glands penis, foreskin
erection, orgasm and ejaculation (male)
*erection, vascular spaces in erectile tissue becomes engorged with blood
*orgasm is culmination of sexual stimulation, accompanied by emission and ejaculation
*emission = movement of semen into the urethra
*ejaculation = movement of semen out of urethra
hormonal control of male reproductive function
*controlled by hormones secreted by hypothalamus, anterior pituitary gland, and testes
*hormones initiate & maintain sperm cell production & oversees development & maintenance of male secondary sexual characteristics
hypothalamic & pituitary hormones
*hypothalamus controls male secondary sex characteristics, changes male body into reproductively functional adult
*gonadotropin-releasing hormone (GnRH)- stimulates anterior pituitary gland to release gonadotropins
*gonadotropins- stimulate activity in gonads and interstitial cell hormones (LH) & (FSH)
*FSH & testosterone- promote spermatogenesis
male sex hormone
*androgens- testosterone is most important one
*interstitial cells produce most of them, adrenal cortex produces small amount
*secretion begins during fetal development
*secretion stops during childhood, begins again during puberty
actions of testosterone
*prior to birth: development of male reproductive organs, descent of testes into scrotum
*during puberty: enlargement of testes (primary sex characteristics) & accessory organs
*development of secondary sex characteristics: body hair, enlargement of larynx, thick vocal cords, thickening of skin, increased muscular growth, thicken & growth of bones
*increases RBC production & cellular metabolism
organs of female reproductive system
primary: two ovaries- produce female sex cells and sex hormones
ovaries
*several ligaments hold ovaries in position
*ligaments include: broad, suspensory, ovarian ligaments
ovary descent
*just like testes in males, the ovaries descend from masses of tissue that lie near kidneys
*ovaries descend to location just inferior to the pelvic brim
*remain attached to the lateral pelvic wall
ovary structure
*subdivided into inner medulla and outer cortex
*medulla is composed of loose connective tissue, blood vessels, lymphatic vessels, & nerves
*cortex contains ovarian follicles & covered by cuboidal epithelium
primordial follicles
*during prenatal development, oogonia divide by mitosis to produce more oogonia in fetal ovaries
*oogonia develop into primary oocytes
*primordial follicle contain primary oocytes & layer of flattened epithelial cells
primary oocytes
*oocytes begin to undergo meiosis, halts until puberty
*number of oocytes steadily declines throughout life of females
*several mil form to embryos (1mil at time of birth)
*400,000 present at puberty, 400-500 release over lifetime
oogenesis
*formation of egg cells
*beginning at puberty, oocytes stimulated to continue meiosis (meiosis I)
*prime oocyte undergoes oogenesis, gives rise to secondary oocyte (reduce number of chromosomes by half) & a polar body
*secondary oocyte may be fertilized.
zygote
fertilized egg
follicle maturation
*FSH initiates follicle maturation, ovaries enlarge
*w/ each reproductive cycle, primordial follicles mature to primary follicles
*primary oocyte enlarge, follicular cells proliferate, zona pellucida forms between oocyte & granulosa
*ovarian cells form layers: inner- produce steroids outer layer- consists of connective tissue
*150days for primordial to become pre-antral follicle
*65-70days for pre-antrial follicle into antral follicle
*only 1 follicle reaches full development
*300days for primordial to develop to antral follicle
ovulation
*release of secondary oocyte from ovary
*secondary oocyte released when follicle ruptures
*post ovulation, secondary oocyte is drawn into uterine tube
female internal accessory organs
*uterine tube
*infundibulum
*fimbriae
*uterus
*vagina
uterine tube
*convey egg cells towards uterus
*each tube expands to form a funnel shaped (infundibulum) encircles ovary
*infundibulum has irregular extensions (fimbriae)
uterus
*receives embryo that develops from fertilized egg cell
*embryo systains in uterus during development
*3 layers: endometrium- inner mucosal layer, myometrium- middle smooth muscle layer,
perimetrium- outer serosa layer
vagina
*extends from the uterus to outside of body
*receives erect peins, conveys urine, secretions
*provides open channel for the fetus during birth
female external reproductive organs
*labia majora
*mons pubis
*labia minora
*clitoris
*vestibule
labia majora
*rounded folds of adipose tissue, encloses & protects external reproductive parts
*corresponds to scrotum of the male
*anterior ends form rounded elevation over symphysis pubis (mons pubis)
labia minora
*flattened, longitudinal folds between labia majora
*protects the opening of the vagina & uterus
clitoris
*small projection at anterior end of vulva
*analogous to the penis
*2 columns of erectile tissue
*produces feelings of pleasure during sexual stimulation
vestibule
*space between labia minora that encloses the vagina & urethral opening
*vestibular glands secrete mucus into vestibule during sex
erection, lubrication, orgasm (female)
*during sex, erectile tissues of clitoris & vestibular bulbs become engorged, vagina expands
*vestibular glands secrete mucus, vestibule & vagina *clitoris responds to stimulation, ends with orgasm
*muscles of the perineum, uterine wall & uterine tubes contract rhythmically, helps transport sperm thru reproductive tract.
hormone control of female reproductive function
*hormones from hypothalamus, anterior pituitary gland, & ovaries, control sex cell maturation
*develop female secondary sex characteristics & changes during menstrual cycle
female sex hormone
*gonadotropin-releasing hormone (GnRH) causes anterior pituitary gland to secrete FSH & LH
*FSH & LH control oocyte maturation & production of female sex hormones
*estrogen & progesterone- important hormones
*estrogen-female secondary sex characteristics
*progesterone-cause changes in the uterus
female reproductive cycle
*GnRH stimulates anterior pituitary gland to secrete FSH-maturation of dominant follicle & LH- stimulates thecal cells to release androgens- converts to estrogen by granulosa cells
*estrogen- maintains secondary sex traits & inhibits release of LH from anterior pituitary gland, & causes dominant follicle to survive
*follicle then produces high levels of estrogen (positive feedback to anterior pituitary gland
ovulaltion
*LH interacts w/ FSH, progesterone, prostaglandins, plasma, & enzymes leading to ovulation
*after ovulation, surge in LH, follicular cells and thecal cells give rise to corpus luteum, secretes estrogen & progesterone
*estrogen stimulates uterine wall, progesterone stimulates endometrium to be more vascular and glandular
menopause
*ovaries cease responding to FSH and cycling ceases
*characterized by low concentrations of estrogen
*50% of women reach menopause by 50years
*20% unusual side effects, 50% degrees of regressive changes: hot flashes, migraines, back aches, fatigue
mammary glands
*accessory organs of female reproductive system *produce specialized secretion (milk)post-pregnancy
*located in subcutaneous tissue of anterior thorax within the breast
structure of mammary glands
*composed of lobes called alveolar glands that contain tubular glands
*separated by dense connective adipose tissue
*connected to the nipple by ducts called alveolar ducts
development of breast
*male & female mammary glands are similar
*males are non-functional
*estrogen stimulates breast development in females
*alveolar glands & ducts enlarge, fat deposited around & within the breast
