Show Menu
Cheatography

The Reproductive systemss Cheat Sheet (DRAFT) by

year one examinations

This is a draft cheat sheet. It is a work in progress and is not finished yet.

male reprod­uctive system anatomy

gonads (testes)
produce sperm & secrete hormones
system of ducts (ductus epidid­ymis, ductus deferens, ejacul­atory duct, urethra)
transport & stores sperm, assists in their matura­tion, conveys them to the exterior
accessory sex glands (Seminal vesicles, prostate gland, bulbou­rethral glands)
adds secretions to semen
supporting structures
scrotum supports testes, penis delivers sperm into female reprod­uctive tract
scrotum
a cutaneous outpou­ching of the abdomen that supports the testes, normal sperm production & survival requires a temper­ature 2-3 degrees below core body temper­ature
testes­/te­sticles
paired oval glands that descend from the abdomen to the scrotum during the 7th month of fetal develo­pment, covered by a fibrous tissue called tunica albuginea, invagi­nations form 200-300 compar­tments called lobules, each lobule is filled with 2 or 3 semini­ferous tubules (sperm­ato­gen­esis)

perineum

- Diamon­d-s­haped area medial to thighs and buttocks of males and females
- Contains external genitalia and anus
- During childbirth the emerging fetus may cause excessive stretching and tearing of the perineum. A physician may make a surgical incision (episi­otomy) in this region to prevent excessive, jagged tears

accessory sex glands

seminal vesicles (60% of vol)
viscous alkaline fluid that helps neutralise acid enviro­nment
 
contains fructose for ATP production by sperm
 
& prosta­gla­ndins contribute to perm motility & viability
prostate glans (25% of vol)
single donut shaped gland that secretes milky, slightly acid fluid
 
it contains 1) citric acid (ATP production via Krebs)
 
2) several proteo­lytic enzymes
 
3) PSA - prostate specific antigen
 
4) semina­lpl­asmin (antib­iotic)
paired bulbou­rethral (cowper's) glands
secrete alkaline fluid that protects passing sperm by neutra­lising acids from urine in urethra
 
mucus lubricates end of penis & lining of urethra

vagina

Fibrom­uscular canal extending from exterior of body to uterine cervix
Mucosa continuous with uterine mucosa
Decomp­osition of glycogen makes acidic enviro­nment hostile to microbes and sperm
Alkaline components of semen raise pH
functions as a passageway for sperma­tozoa & the menstrual flow, the receptacle of the penis during sexual interc­ourse, and the lower portion of the birth canal
4 inch long fibrom­uscular organ ending at cervix
- mucosal layer
- muscularis layer is smooth muscle allows consid­erable stretch
- adventitia is loose connective tissue that binds it to other organs

fallopian tubes

provide route for sperm to reach an ovum
site of fertil­isation
transport secondary oocytes & fertilised ova from ovaries to uterus
Infund­ibulum ends in finger­-like fimbriae; Produce currents to sweep secondary oocyte into tube
Ampulla – widest longest portion
Isthmus – joins uterus
Three layers:
1) Mucosa – ciliary conveyor belt,
peg cells provide nutrition to ovum
2) Muscularis – perist­altic contra­ctions
3) Serosa – outer layer

oogenesis & follicular develo­pment

- results in formation of a single haploid secondary oocyte
- during early foetal develo­pment, primordial primitive germ cells migrate from yolk sac to ovaries
- differ­entiate into oogonia - diploid 2n stem cells
- before birth, most germ cells degenerate - atresia
- a few develop into primary oocytes that enter meiosis I during foetal develo­pment
- Each covered by single layer of flat follicular cells – primordial follicle
- About 200,000 to 2,000,000 at birth in each ovary, 40,000 remain at puberty, and around 400 will mature and ovulate during a lifetime
 

Testes cells

leydig cells (inter­stitial endocr­ino­cytes)
found in spaces between adjacent semini­ferous tubules secrete the male hormone testos­teone
sertoli cells
embedded among sperma­togenic cells in tubules , form blood testes barrier, nourish sperma­toc­ytes, mediate effects of testos­terone & FSH on sperma­tog­enesis, phagoc­ytose excess sperma­tids, secrete inhibin hormone which helps regulate sperm production by inhibiting production of FSH

mammary glands

modified sudori­ferous (sweat) glands that produce milk (lacta­tion)
15-20 lobes divided into lobules composed of alveoli (milk-­sec­reting glands)
Milk secreting glands open by lactif­erous ducts at the nipple
Areola – pigmented area around nipple

external female genitalia

Mons pubis
fatty pad cushions pubic symphysis
Labia majora
homologous to scrotum
Labia minora
homologous to spongy (penile) urethra
Clitoris
small mass of erectile tissue and numerous nerves­/blood vessels homologous to glans penis
Vestibule
region between labia minora
Bulb of the vestibule
2 elongated masses of erectile tissue on either side of vaginal orifice

secretions & functions

Secretory cells of the mucosa of the cervix produce a cervical mucus (a mixture of water, glycop­rotein, serum-type proteins, lipids, enzymes, and inorganic salts)
- when thin, is more receptive to sperm
- when thick, forms a cervical plug that physically impedes sperm penetr­ation
- mucus supple­ments the energy needs of the sperm

The cervix and the mucus also play a role in capaci­tation - renders them competent to fer­tilise an oocyte

oogenesis

- Once secondary oocyte is formed it begins meiosis II but stops at metaphase
- At ovulation, secondary oocyte expelled with first polar body
- If fertil­isation does not occur, cells degenerate
- If a sperm penetrates secondary oocyte, meiosis II resumes
- Secondary oocyte splits into 2 cells of unequal size -second polar body (disca­rded), ovum or mature egg
- Nuclei of sperm cell and ovum unite to form diploid zygote- fertil­isation

follicular develo­pment

Each month from puberty to menopause, FSH and LH stimulate the develo­pment of several primordial follicles (one reaches ovulation)

Just before ovulation, diploid primary oocyte completes meiosis I

Produces 2 unequal sized haploid (n) cells – secondary oocyte
and first polar body (disca­rded)

female reprod­uctive system

ganads (ovaries)
produce secondary oocytes & hormones
uterine fallopian tubes or oviducts
transport fertilised ova
uterus
where foetal develo­pment occurs
vagina
external organs
vulva or pudendum
mammary glands
produce milk

penis

- passageway for ejacul­ation of semen
- body composed of 3 erectile tissue masses filled with blood sinuses surrounded by smooth muscle & elastic connective tissue
erection: parasy­mpa­thetic fibers releas­e/cause local production of nitric oxide, dilates arterial smooth muscle, large amounts of blood enter blood sinuses, compresses veins draining the penis

sperm morphology

adapted for reaching & penetr­ating a secondary oocyte
head contains DNA (23 Chromo­somes) & acrosome
acrosome has enzymes that help sperm penetrate secondary cycle (hyalu­ron­idase & protei­nase)
midpiece contains mitoch­ondria to form ATP
produced at rate of 300 millio­n/day
life expectancy = 48hrs in female reprod­uctive tract
 

ovaries

- paired glands homologous to testes
- produce: gametes (secondary oocytes that develop into mature ova after fertil­isa­tion, & hormones including proges­terone, estrogens, inhibin & relaxin

ligaments hold ovaries in place:
1. broad ligament - a fold of parietal peritoneum
2. ovarian ligament - anchors ovaries to uterus
3. suspensory ligament - attaches ovaries to pelvic wall
histology:
- germinal epithelium covers surface of ovary
- tunica albuginea located underneath epithelium
- ovarian cortex = ovarian follicles & stromal cells
- ovarian medulla contains blood vessels, lymphatic vessels & nerves
- ovarian follicles in cortex consist of oocytes in various stages of develo­pment
- mature graafian follicle is a large, fluid-­filled follicle ready to expel secondary oocyte during ovulation
- corpus luteum - remnants of mature follicle after ovulation

uterus (womb)

Functions
- the transport of sperma­tozoa, menstr­uation, implan­tation of fertilised ovum, develo­pment of foetus during in pregnancy and labour

Anatom­ically – can be subdivided into:
- Fundus
- Body
- Isthmus
- Cervix (opens into vagina)

blood supply:
Uterine arteries branch as arcuate arteries and radial arteries that supply the myometrium

Straight & spiral branches penetrate to the endome­trium
- spiral arteries supply the stratum functi­onalis
- their constr­iction due to hormonal changes starts menstrual cycle
histology: 3 layers
(1) Perime­trium – outer layer
(2) Myometrium
- 3 layers of smooth muscle
- contra­ctions in response to oxytocin from posterior pituitary
(3) Endome­trium – inner layer
- highly vascul­arized

Stratum functi­onalis
- lines cavity, sloughs off during menstr­uation

Stratum basalis
- permanent, gives rise to new stratum functi­onalis after each menstr­uation

male reprod­uctive ducts

ducts of testis
series of coiled efferent ducts that empty into epiidi­dymis
epididymis
site of sperm maturation & storage
ductus (vas) deferens
conveys sperm during sexual arousal through perist­altic contra­ctions
spermatic cord
ductus deferens ascends out of scrotum with arteri­es/­veins, autonomic nerves, lymphatic vessels & cremaster muscle
ejacul­atory ducts
formed by union of ducts from seminal vesicle & ductus deferens, termin­ating in the prostatic urethra
urethra
shared terminal duct of reprod­uctive & urinary systems, subdivided into: prostatic urethra, membranous urethra, spongy penile urethra

sperma­tog­enesis

produces haploid sperm (n) = one set of 23 chromo­somes from diploid sperma­togonia (2n)
takes approx. 74 days
meiosis I - process = reduction division, homologous pairs line up to form a tetrad (4 chromatids from each homologous pair) & the two cells formed by this nuclear division are called secondary sperma­tocytes (haploid)
each of 23 chromo­somes is still made up of 2 chromatids attached at centromere
goes through meiosis II = equatorial division, 2 chromatids separate (no DNA replic­ation)
results in 4 spermatids - each haploid & unique, 50% X chromosome & 50% Y.
spermi­oge­nesis = develo­pment of spermatids into sperm, acrosome & flagella (tail) form, mitoch­ondria multiply

spermi­ation = release from connec­tions to sertoli cells

female reprod­uctive cycle

Encomp­asses ovarian and uterine cycle, hormonal changes that regulate them, and related changes in breast and cervix
controlled by monthly hormone cycle of anterior pituitary, hypoth­alamus and ovary
ovarian cycle: changes in ovaries that occur during and after maturation of oocyte

Uterine (menst­rual) cycle: concurrent series of changes in uterine endome­trium preparing it for arrival of fertilized ovum. if implan­tation does not occur the stratum functi­onalis is shed during menstr­uation