chapter 4 Flashcards
External female genitalia
- clitoris
- labia majora
- labia minora
- mons pubis
- vulvar vestibule
- urethral opening
- vaginal opening
internal female genitalia
- Vagina
- bartholin glands
- skene’s glands
- cervix
- uterus
- ovaries
- fallopian tubes
male external genitalia
- penis
- scrotum
male internal genitalia
- testes
- epididymis
- seminiferous tubules
- vas deferens
- seminal vesicles
- prostate glands
- cowpers glands
spermatogenisis
sperm production
OS (in relation to female anatomy)
- opening in centre of cervix
cilia
- micro hair-like projections
rugae
- rigid walls
mons pubis
- rounded fatty pad of tissue covering pubic symphysis
- sensitive to touch
- covers in pubic hair
pubic symphysis
where right and left pelvic bones meet
theories for why we have pubic hair
- visual sign of sexual maturity
- provides protective padding during friction of intercourse
- plays role in sexual communication thought pheromonal signalling by helping to dissipate volatile compounds
the clitoris
- only known function is pleasure
- approx same nerve ending as penis
- two external components: glands and shaft
- two internal cura (roots) the project inwards from either side of shaft
- glans + shaft = covered by prepuce
- corpus cavernosa and vestibular bulb line vagina and swell
labia majora
- extends down from mons pubis
- padding and protection for inner structures
- many nerve endings
labia minora
- hairless skin folds between majora
- extends upwards and forwards toward clit
-contains: sweat/oil glands, nerve endings and blood vessels
what external genitalia is the prepuce/clitoral hood
labia minora
fourchette
area where labia minora meets posterior to vaginal opening
vulvar vestibule
- entranceway
- teardrop shaped of vulva inside labia minora
provoked vestibulodynia
condition that causes pain in vulvar vestibule rather than pleasure
urethral opening
- halfway between clit and vaginal opening in vestibule
- transmits pee form bladder to outside world
vaginal opening
- highly sensitive
- located in posterior area of vulvar vestibule
- below urethral opening
hymen
- thin membrane that covers vaginal opening
- believed to protect vaginal tissue in early life
Vagina
- canal that starts at vaginal opening and extends up and back towards base of spine
- connects with cervix
average length of vagina
7.5-12.5cm but grows 5-7.5cm more when aroused
average penis length and girth
- flaccid: L=9.2cm, G=9.3cm
- errect: L=13.1cm, G=11.7cm
labiaplasty
- most common voluntary genital alteration process
- not always cosmetic (pain)
Three layers of tissue in the vagina
- vaginal mucosa (outermost, rigid walls are soft, moist and release secretions that maintain slight acidic balance, releases lubricant)
- middle layer (muscular and in lower third of vagina, tighten during arousal, contract rapidly and rhythmically during orgasm)
- deepest layer (fibrous tissue, keeps vagina in place within pelvis)
lower third of vagina is _____ whereas the upper third is _______
sensitive, insensitive
bartholin glands
- small pair of glands that lie inside labia minora on left and right side of vagina
- unknown function
skenes glands
- pair by front walls of vagina
- close to urethra
- ducts empty into urethra
- contribute to sensitivity of g spot
g spot
- highly sensitive on front vaginal wall, 5cm from opening
cervix and uterus
- lower third of uterus
- top of vagina, contains mucus secreting glands
- can be tilted forward (anteflexed) or backwards (retroflexed)
3 layers of uterus
- endometrium (innermost, hormone secreting, sheds during menstruation)
- myometrium (muscular, stretches and contracts for fetus)
- perimetrium (deepest, smoothest membrane)
ovaries
- produces ova (eggs)
- typically 2, one on each side of uterus
- endocrine glands that produce estrogens and progestins
- when born=2 million ova
- when first menstruation occurs=300 thousand
- two can release at once (frat twins)
sperm travel from vagina to uterus via _____
os
fallopian tubes
- transports ova from ovaries to uterus
- 10cm long
- eggs move via cilia and muscle contractions
infundibulum
- closest to ovary, where fertilization occurs
- finger like projection (fimbriae) extend to ovaries and draw egg out
penis only consists of ____ muscles
smooth
3 sections of penis
- glands (most sensitive, the head)
- shaft (main external part, hairless loose skin when flaccid, starts at base and ends at corona/rim of glands)
- roots (extended internally and attach to bar of pubic bone)
prepuce (male)
- foreskin
- partially covers glands
- retractable skin fold
approx _____% of men in canada and world wide are circumcized
30%
scrotum
- loose pouch of skin containing testes
- under base of penis
- two thin layers: outer (skin w little hair) and inner (sheet of involuntary muscles - dartos)
- dartos respond to temperature (retract if cold and hand low if hot)
3 spongy bodies in penis
- corpora cavernosa: 2 larger ones, side by side on upper shaft
- corpus sponiosum: length of penis w urethra in middle, raises on underside when erect
difference between corpora cavernosa and corpus sponiosum
- corpora cavernosa: hardens
- corpus sponiosum: stays flexible to allow urethra to have room for ejactulate to pass
Why do penis get ‘hard’
- elevated BP compresses veins that usually draw out blood, trapping it
main neurotransmitter used in erections
- nitric oxide
- causes smooth muscles to dilate)
what neurotransmitter is mainly responsible for loosing an erection
- norepinephrine and epinephrine
- stimulate muscles on the walls of arteries to constrict
testes
- 2 inside scrotum
- suspended by spermatic cord
- usually form in around last month before birth in utero
in urtero, where are testes formed
the abdomen
cremaster
- muscle surrounding spermatic cord
- lifts testes
t or f: testes should always be slightly warmer than the body temperature to keep sperm healthy
- false, they should be slightly cooler
- lower sperm counts seen in men whose testes are in hot environments often
epididymis
- c shaped, covers part of each testes
- narrow, tightly coiled tube
- consists of: head body and tail
- mature sperm is brought back here and stored
seminiferous tubules
- interstitial cells that are between tubules
- sperm production and storage
- long, thin, coiled tubes packed in testes (think intestines)
interstitial cells produce _____ that is secreted directly into bloodstrem
androgens
vas deferens
- sperm stored in epididymis drain here
- carried sperm up the abdominal wall, around bladder and to prostate gland
- delivers sperm into urethra via cilia and muscle contractions
t or f: its only after ejaculation that sperm swim independently
true
seminal vesicles
- two tubular glands next to prostate gland
- near end of vas deferens
- secretes surgary alkyd fluid (70% of ejaculate)
prostate gland
- directly below bladder
- grandular tissue surrounded by muscle
- secretes thin, alkaline fluid ot maintain sperm
- semen makes vagina safe for sperm (acid/base)
cowpers glands
- two pea sized structures on sides of urethra, below prostate
- ducts empty into urethra
- secrete pre-ejactulate (prepares urethra for seminal fluid)
there are ______ sperm in ejaculate and it makes up ___% of ejaculate
200-500 million, 2%
each ejaculation releases ____ of semen
- 3ml
- can be more depending on age, last time of ejaculation (longer=more), and length of arousal before ejaculation (longer=more)
Masters and johnson’s 4 phases of the sexual response cycle is based on ______ and _____
vasocongestion, myotonia
