BIOL201 - Reproductive System

What is the overall function of the reproductive system? how is this different from other systems?

ensures survival of a species by production of offspring --> other systems are typically to maintain homeostasis

what are the 4 basic functions of the reproductive system?

1. production of gametes (sperm and oocytes)

2. transport/maintenance of gametes

3. nurture the developing offspring

4. production of hormones

Compare the primary and secondary sex organs

primary (gonads) --> testes in males, ovaries in females

secondary (accessory) --> ducts, glands, penis in males, uterine tubes, uterus, and vagina in women

what does fertilization require?

"delivery" of gametes --> requires sperm cell and secondary oocyte

why is location an optimal condition of fertilization?

wrong location leads to ectopic pregnancy (can result in death!)

compare pre-birth and post-birth nourishment of a fetus

pre-birth --> fetal development requires prenatal vitamins

post-birth --> idk, food?

what is production of reproductive hormones required for? what hormones are produced?

testosterone, progesterone, and estrogen --> growth and development of sex organs and gamete (primary) and secondary sex characteristics

what are secondary sex characteristics?

internal and external anatomical and physiological features (body hair, voice, skeletal muscle)

what are the 2 main functions of the male reproductive system?

1. synthesis and delivery of sperm cells (genetic plan for offspring in DNA)

2. synthesis and secretion of testosterone

what is the formula for testosterone? what is it required for?

C19H28O2 --> required for sperm development, tissue growth, and secondary sex characteristics

what is the perineum? what does it border (3)? what does it contain?

diamond-shaped region between thighs --> borders pubic symphysis, ischial tuberosities, and coccyx --> contains external genitalia (scrotum and penis)

what is the scrotum?

pouch of skin, muscle, and fibrous connective tissue containing the testes

what is the perineal raphe? what does it mark?

medial seam on scrotum surface --> marks location of median septum

what are the 3 physical characteristics of the scrotum and testes?

1. left testicle descends lower than the right

2. skin has sebaceous glands (oily secretion) with sparse hair, rich sensory innervation, and dark pigmentation

3. internal median septum divides scrotum into right and left compartments

what is the spermatic cord? what does it contain?

bundle of fibrous connective tissue containing the ductus deferens, blood and lymphatic vessels, and testicular nerve

compare the external and internal inguinal rings

external --> inferior entrance to inguinal canal

internal --> superior exit to pelvic cavity

why are the human testes external to the body?

sperm production decreases at core body temperature, needs to be kept at a lower temperature (less than 37)

what is involved in temperature regulation mechanisms? what does it consist of?

the cremaster muscle --> internal abdominal oblique muscle

how does the cremaster muscle regulate temperature of the testes

in cold temps --> contract and draws testes upward towards body

in warm temps --> relaxes and suspends testes further from body

what is the dartos fascia?

subcutaneous layer of smooth muscle containing the dartos muscle

what is the function of the dartos muscle? why does this work?

smooth muscle contracts when cold, wrinkling the scrotum, holding the testes against warm body --> reduces surface area of the scrotum and heat loss

what are the functions of the ductus deferens and epididymis

exocrine function

compare the exocrine and endocrine functions of the testes and their destination

exocrine gland --> sperm cells --> one destination (urethra)

endocrine gland --> testosterone --> many destinations (such as cardiovascular system)

what is the tunica albuginea?

connective tissue that divides testis into lobules

summarize the path of sperm exiting the testes

seminiferous tubules --> tubulus rectus --> rete testis --> epididymis --> ductus deferens --> ejaculatory duct

what occurs in the epididymis? what does it contain

site of sperm maturation (acrosome maturation) --> contains stereocilia

what is the purpose of stereocilia?

increases surface area to facilitate absorption or fluid from lumen of the duct

what does the ductus deferens merge with? where?

merges with duct of seminal vesicle --> in enlarged distal end of ductus deferens ("ampulla")

what is the function of the walls of the ductus deferens?

smooth muscle that generates peristalsis (semen ejaculation)

what is the purpose of merging with the seminal vesicle in the ejaculatory duct (and end of ductus deferens)?

adds secretions to the sperm

where does the ejaculatory duct end? what is the importance of this?

ends at urethra within prostate gland --> adds secretions to sperm

what are the 2 functions of the penis?

urination and ejaculation

what are the 2 main structures of the penis?

1. corpora cavernosa

2. corpus spongiosum

compare the corpora cavernosa and corpus spongiosum

corpora cavernosa --> spongy tissue channels that fill with blood (target of viagra and cialis)

corpus spongiosum --> maintains opening of urethera (pliable tissue)

what does the root of the penis consist of?

crura and bulb

what is the glans penis? what is it covered by?

enlargement of corpus spongiosum --> covered by prepuce/foreskin (target of circumcision)

what are the 3 main accessory organs of the male reproductive system?

seminal vesicles, prostate gland, and bulbourethral glands ("Cowper's glands")

Where do the seminal vesicles empty? what do they produce?

empties into ejaculatory duct --> produces about 60% of semen

what do the seminal vesicle secretions include? (3)

1. fibrinogen --> weak coagulant that thickens semen

2. high pH that neutralizes acidic mucous

3. fructose

What does the prostate gland secrete? what does it contain and what is its purpose?

produces about 30% of semen at high pH --> contains clotting factors and fibrinolysin (PSA) that inactivates fibrin

What does the bulbourethral glands secrete? what are the glands considered?

contribute about 5% to semen and mucous secretion --> paired glands

what is the importance of the bulbourethral glands mucous secretion? what does it contain?

contains glycoproteins that act as urethral lubrication prior to ejaculation --> helps neutralize pH of female vagina

what does emission of semen consist of? what does this allow for?

discharge of semen into prostatic urethra --> adds secretions from accessory glands

what are secretions from glands triggered by? what does this cause?

parasympathetic nervous system --> vasodilation

what does ejaculation consist of? what is this triggered by?

expulsion of semen from urethra by peristalsis --> triggered by sympathetic nervous system activation

what is there temporary coagulation in the semen?

coagulation as fibrinogen becomes fibrin, then fibrinolysis breaks up the coagulation

what happens to most sperm cells after ejaculation? why?

most "die off" before reaching uterine tubes --> loss of acrosome

What are the 2 functions of the female reproductive system?

1. synthesis and delivery of mature oocyte (egg) --> genetic plan for offspring (DNA)

2. synthesis and secretion of progesterone and estrogens (plural!!)

what is the chemical formula for estrogen? what does this cause in the body?

C18H19NaO5S --> follicle and oocyte development, and secondary sex characteristics

what is the Graafian follicle?

A mature follicle of the ovary --> develops ovum for release

compare the urethra in men and women

men --> 2 functions (piss and cum?)

women --> only 1 function (piss?)

what is the external female genitalia also referred to as? (2)

vulva or pudendum

what is the vestibule? how is the labia minora related?

region of vaginal and urethra opening --> labia minora forms borders on sides

what is the clitoris?

erectile tissue

what does the corpora cavernosa form in women? what is not involved

the crus of the clitoris, the corpora spongiosa is NOT involved

what does the labia majora form? what is this?

unite to form the mons pubis --> subcutaneous fat

what is the vaginal orifice? what is this homologous to in men?

in lateral margins, erectile tissue called bulb of the vestibule --> homologous to corpus spongiosum in men)

compare the positions of the clitoris, urethra, and vagina

clitoris is most anterior, then urethra, then vagina

what is the vagina? what does it allow for?

female organ of copulation (intercourse) --> allows menstrual flow and childbirth

what is the purpose of Hymen? what happens after intercourse?

covers the vaginal opening (vaginal orifice) and is perforated with holes --> becomes enlarged with 1st sexual intercourse

what is the role of muscular walls with mucous membrane?

contain smooth muscle rugae (folds) that allow expansion for childbirth

what is the fornix?

superior domed portion attached to sides of cervix

what are the 4 regions of the uterus?

cervix (inferior), body, isthmus, and fundus (superior)

what are the 3 layers of the uterine wall? what type of membrane/muscle are they?

1. endometrium --> mucous membrane

2. myometrium --> smooth muscle

3. perimetrium --> serous membrane

what is the functional layer of the uterus? what is the basal layer?

functional --> innermost (endometrium) --> replaced monthly during menstrual cycle

basal --> deepest layer

what is the function of the mesosalpinx?

part of broad ligament that opens directly into peritoneal cavity --> receives oocyte from ovary

what is the fimbriae? where is it found?

long thin processes that extend from the infundibulum (catches egg)

what are the 3 layers of the uterine tube (fallopian tube) wall?

1. outer serosa

2. middle muscular layer

3. inner mucosa

what is the function of the uterine tube (fallopian) wall (2)?

provides nutrients for oocyte/embryonic mass --> cilia moves fluid and oocte/embryonic mass through the tube towards uterus

what is the ampulla? what is its function?

widest part of fallopian tubes (uterine tube) --> where fertilization occurs

what are the 3 ligaments of the uterus?

broad, round, and uterosacral

compare the round and uterosacral ligaments in terms of location

round --> from uterus through inguinal canals to labia majora

uterosacral --> attach lateral wall of uterus to sacrum (very literal name)

what is unique about the cervix? what does it contain?

more rigid and less contractile than rest of uterus --> contains cervical canal lined with mucous glands

how are the 5 main arteries bringing blood into the female reproductive system?

1. ovarian artery

2. uterine artery (from internal iliac)

3. vaginal artery (from internal iliac)

4. arcuate artery

5. spiral arteries

what do the spiral arteries bring blood flow to?

myometrium and endometrium

what is the breast?

tissue overlying the pectoralis major muscle

when does the mammary gland develop and when is it active?

develops within breast during pregnancy --> remains active in the lactating breast

what are the 3 main structures of the breast?

1. body

2. areolar glands

3. the non-lactating breast

what is the areolar gland?

intermediate between sweat glands and mammary glands (around nipple)

what is the non-lactating breast made of? what does it attach?

made of adipose and collagenous tissue --> suspensory ligaments attach breast to dermis of overlying skin and fascia of the pectoralis major

compare the functions of prolactin and oxytocin

prolactin --> anterior pituitary --> causes breast development

oxytocin --> posterior pituitary --> causes lactation after child birth

why do mature breasts have alveoli?

site of lactate production