Module 6: Reproduction Flashcards
gonads
organs where gametes are produced
gametes
sex cells
testes produce
spermatozoa
ovaries produce
oocytes
pelvis is made up of
hip bones + sacrum + coccyx
is the pelvic inlet or pelvic outlet open and bigger
inlet
false/ greater pelvis
superior region, above pelvic inlet, contains GI tract
true/ lesser pelvis
inferior region, between inlet and outlet, contains internal reproductive organs
female pelvis is larger due to
allowing for space to fit a fetus and birth canal during pregnancy
two muscles of the pelvic floor
levator ani and coccygeus
openings in pelvic floor
urethra, anal canal and vagina in females
anterior male triangular division
urogenital triangle- urethra opening and external genetalia
posterior male triangular division
anal triangle- anal canal and fat
function of male reproductive system
to produce spermatozoa and transport spermatozoa into female reproductive tract
male reproductive system is made up of
testes, reproductive tract, accessory structures and glands
path sperm travel along
testes–> epididymis–> ductus (vas) deferens–> ejaculatory duct–> urethra
the scrotum contains
two testes, two epididymides, two spermatic cords with ductus deferens
function of testes
to produce sperm, testosterone and inhibin
location of testes
lie in scrotum outside the body
structure of testes
surrounded by dense fibrous capsule
seminiferous tubules are located
within the testes
tubules join to form
rete testis
interstitial endocrine (Leydig) cells produce
testosterone- outside tubules
nurse (Sertoli) cells produce
inhibin- inside tubules
spermatogenic cells
spermatozoa at various stages of development
epididymis has three regions
head, body, tail
function of epididymis
site of sperm maturation
structure of ductus deferens
covered by smooth muscle and dilates to form the ampulla
Ejaculatory ducts are formed by
the union of the duct from the seminal vesicle and the ampulla
function of male urethra
urination and ejaculation
three sections of male urethra
prostatic, membranous and penile/ spongy
why are the testes house outside the body
ideal temp for sperm production is around 34 degrees
what muscle lines the scrotum
dartos
cremaster muscle
contracts for heat conservation and arousale
spermatic cord contains
ductus deferens, blood vessels, nerves and lymphatics
3 regions to the penis from top to bottom
root (bulb), body and glans covered by prepuce/ foreskin
the penis contains three cylindrical erectile tissues
two corpus cavernosa and one corpus spongiosum
corpus cavernosa
main erectile tissue
corpus spongiosum
contains urethra
semen is made up of
spermatozoa and seminal fluid
seminal fluid is produced by three glands
seminal vesicle, prostate gland and bulbourethral gland
how much semen is produced by seminal vesicles
60%
how much semen is produced by prostate gland
30%
PSA
prostate-specific antigen
function of PSA
contributes to sperm activation, viability and motility
how much semen is produced by bulbourethral gland
5%
the last 5% of semen is made of what?
sperm
what is a vasectomy
surgical method of sterilisation in males, cut the ductus deferens
what affect does a vasectomy have on volume of seminal fluid
volume of seminal fluid stays the same, the sperm is just removed
gametogenesis
formation of the gametes
spermatogenesis
formation of spermatozoa from spermatogonia
oogenesis
formation of oocytes from oogonia
gametogenesis occurs through
meiosis and mitosis
meiosis I
2 haploid cells produced from 1 original diploid cell
meiosis II
each cell produced from meiosis I divides to produced 2 haploid cells
spermatogenesis occurs in
seminiferous tubules
spermatogenesis 1
spermatogonia divide by mitosis into 2 daughter cells, one spermatogonium (A) stays at the basement membrane of the seminiferous tubule
spermatogenesis 2
the second spermatogonia (B) differentiates into a primary spermatocyte which undergoes meiosis I, forms 2 secondary spermatocytes
spermatogenesis 3
these undergo meiosis II to form spermatids, these then differentiate into spermatozoa with heat, body and tail via spermiogenesis
Gonadotropin
hormone that acts on the gonads
GnRH
gonadotropin releasing hormone produced by hypothalamus
LH
luteinizing hormone (a gonadotropin) produced by the anterior pituitary
FSH
follicle stimulating hormone (a gonadotropin) produced by the anterior pituitary
function of testosterone
responsible for the male characteristics
negative feedback loop in males
LH stimulates production of testosterone, FSH and testosterone control spermatogenesis, FSH stimulate inhibin production, inhibin suppresses FSH and testosterone suppresses LH and GnRH
function of the female reproductive system
to produce oocytes, transport ova and sperm to the appropriate site for fertilisation and to provide a site for the developing embryo and fetus to grow.
the female perineum is located
in the region inferior to the pelvic floor and between upper region of the thighs
urogenital triangle in females contains
external genitalia= vulva
anal triangle in females contains
anus
mons pubis
in front of the pubic symphysis
labia
2 lip-like structures
major (labia majora)
larger and more lateral
minor (labia minora)
smaller and more medial
space between labia is called
vestibule
clitoris
complex erectile organ
clitoris contains
glans, body, crura (2), bulbs (2)
structures in the female reproductive tract
ovary, uterine tubes, uterus, cervix, vagina
most lateral part of the uterine tube
infundibulum
mid portion of uterine tube
ampulla
most medial portion of uterine tube
isthmus
layers of the uterus from outermost to innermost
perimetrium, myometrium and endometrium
what is perimetrium made from
connective tissue
what is myometrium made from
smooth muscle (thickest layer)
what is endometrium made from
columnar epithelium, uterine glands and arteries
layers of the cervix from outermost to innermost
external os, cervical canal, internal os
function of the cervix
provides passage between uterine cavity and vagina and produces cervical mucus
blood supply to ovaries
ovarian artery
blood supply to uterus
uterine artery
blood supply to vagina
vaginal arteries
spiral arteries are
uterine arteries
the main site of blood loss during periods are
the spiral arteries
the outer cortex of the ovary contains
follicles
the inner medulla of the ovary contains
connective tissue, blood/ lymphatic vessels and nerves
the ligaments of the female reproductive system are
broad ligament, ovarian ligament, suspensory ligament and round ligament
function of peritoneum
fold and press over structures to create other ligaments
mesometrium means
of the womb
mesosalpinx means
of the tube
mesovarium means
of the ovary
vesicouterine pouch
continuous fold of broad ligament (visceral peritoneum) over anteriorly located bladder
rectouterine pouch
continuous fold of broad ligament (visceral peritoneum) over posteriorly located rectum
function of breasts
nourish infants
what hormones stimulate development of breast tissue
estradiol and progesterone
structures of the breasts
lobes–> lobules–> alveoli–> lactiferous ducts–> lactiferous sinuses
where do oocytes develop
within ovarian follicles (1 oocyte per follicle)
oogenesis- before birth
oogonium in gonad, population increase by mitosis (stop before birth). Oogonia differentiate to form primary oocytes which then start meiosis which halts at prophase one until puberty
primary oocytes are in encased in what
primordial follicle
oogenesis- from menarche till menopause
under GnRH influence small number of follicles are recruited for ovarian/menstrual cycle. only one oocyte completes development within dominant follicle. this completes meiosis I forming a secondary oocyte and 1st polar body. this then starts meiosis II and halts at metaphase II until fertilisation
most primary oocytes undergo what
atresia
atresia is
the process of degradation
follicles are multi layered
granulosa cells and theca cells
granulosa cells produce
estradiol
ovulation
oocyte and corona radiata released into peritoneal cavity
GnRH (hypothalamus)
release of FSH and LH
FSH (anterior pituitary)
stimulates the growth of ovarian follicles
LH (anterior pituitary)
surge of LH involved in ovulation, formation of corpus luteum
Estradiol (developing follicles)
assists follicle growth with FSH and female characteristics
Inhibin (granulosa cells)
negative feedback to anterior pituitary to suppress FSH
Progesterone (corpus luteum)
negatively feeds back to suppress GnRH (therefore LH and FSH), maintains pregnant state
ovarian/ menstrual cycles
the regular cyclic changes in the ovary and uterus that prepare an oocyte/ ova for fertilisation and the endometrium for embryo implantation
follicular phase (preovulatory phase) happens within
days 1-14
luteal phase (postovulatory phase) happens within
days 15-28
follicular phase
- increased FSH from the anterior pituitary
- stimulates follicular growth
- growing follicles secrete estradiol and inhibin
- reduced FSH from anterior pituitary
- growing follicles undergo atresia except dominant follicle
- dominant follicle secretes large amounts of estradiol
- high estradiol stimulates surge of LH
- follicle ruptures and ovulation occurs
- oocyte enters peritoneal space/collected into uterine tube
luteal phase
- ovulated follicle collapses and forms corpus luteum
- secretes progesterone, estradiol and inhibin
- these decrease FSH and LH secretion
- negative feedback on hypothalamus
- if fertilisation and implantation does not occur the corpus luteum involutes
- fall in progesterone and estradiol
- removes negative feedback on FSH and LH
menstrual and proliferative phase happens
days 1-14
secretory phase happens
days 15-28
menstrual and proliferative phase
- endometrium breaks down and bleeds during menstruation
- estradiol stimulates endometrial growth from days 6-14
- rapid tissue growth inclduing growth of glands and vasculature
secretory phase
- after ovulation corpus luteum secretes progesterone
- progesterone promotes endometrial maturation
- glands become secretory
- spiral arterioles grow and coil
secretory phase back to menstrual phase
if fertilisation and implantation do not occur;
- corpus luteum artophies.
- progesterone levels fall
- spiral arteries contract
- endometrial tissue breaks down and bleeding occurs
- shed tissue and blood removed via cervix and vagina
coitus
sexual intercourse
process of coitus
semen released into upper part of vagina so that sperm can travel to appropriate site for fertilisation
stages of the male sexual act
erection of the penis (parasympathetic), mucus secretion into urethra, ejaculation and resolution
stages of ejaculation
emission and expulsion
nerve supply of the penis
richly supplied by sensory and motor nerves
pudendal nerve supplies
sensory and somatic motor innervation to perineum and external genitalia including penis
parasympathetic (erection)
stimulates production of Nitric oxide (vasodilator) by deep arteries of the penis
sympathetic (ejaculation)
stimulates contraction of smooth muscle
somatic motor (ejaculation)
stimulates contraction of skeletal muscles around bulb of penis
erection
-parasympathetic response to stimuli allows arteries to dilate , erectile tissue becomes engorged with blood
intromission
erect penis entering vagina
emission
sympathetic response of smooth muscle and ductus deferens contracting to move sperm into ampulla allowing it to be moved with seminal fluid into urethra
expulsion
semen in urethra activates somatic sympathetic reflexes and the urethral smooth muscle and pelvic floor contracts so semen is ejected
resolution
blood flow to penis is reduced and penis becomes flaccid
stages of the female sexual act
are similar to males as the clitoris gets engorged with blood in response to stimuli, lubricating fluid is secreted, the vagina becomes wider and longer and the vaginal, uterine and perineal muscles contract
insemination
semen released into upper part of vagina
ampulla
site of fertilization
contraception
any method to prevent pregnancy
natural methods include
periodic abstinence (rhythm method), withdrawal method (coitus interruptus) and lactational infertility
artificial methods include
barrier, hormonal, intrauterine devices and sterilisation
which contraception method has highest failure rate
natural methods
barrier methods include
caps, diaphragms and condoms
hormonal methods include
combined oral contraceptive pills, progestin-only contraception (implants and IUDs)
IUD methods include
copper IUD and hormonal IUD
sterilisation involves
tubal ligation (females) and vasectomy (males)
the only contraceptive that prevents STIs is
condoms
what is the copper IUD toxic to
oocyte and zygote
