Reproductive System

common elements of both male and female repro system

common elements of both male and female repro system

• have primary reproductive organs (gonads)

  • testes

  • ovaries

• produce large amounts of sex hormones

• have accessory reproductive organs

  • towards the site of fertilization (females)

  • towards the outside of the body (males)

gametes

• produced by both males and females

• female: releases a single gamete monthly

  • oocyte

• male: produces large # of gametes

  • 100 million/day

  • stored for short time

  • if not expelled = reabsorbed

commonalities between the male and female repro system

• sexual union, copulation, coitus, sexual intercourse

• hormones

• support, protection, nourishment (mostly in females)

puberty

• onset during adolescence

• initiated by the hypothalamus

• the GnRH hormone acts on the pituitary to release FSH and LH

• gonads start to secrete sex hormones + gametes mature

• external sex development

  • enlarged breasts (female)

  • pubic and facial hair (males)

hormones initiating puberty

• hypothalamus releases GnRH

• stimulates the antierir pituitary to release…

  • FSH

  • LH

perineum

• urogenital triangle

• anal triangle

urogenital triangle

• urethral and vagina (female)

• penis and scrotum (male)

anal triangle

• anus and external anal sphincter

female primary reproductive organs

ovaries

female accessory reproductive organs

• uterine tubes

• uterus

• vagina

• external genitalia

• mammary glands

ovaries

• paired, oval organs

• within the pelvic cavity lateral to the uterus

• slightly larger than an almond in an adult (size varies based on menstrual cycle + pregnancy)

• surrounding the ovary is a simple cuboidal layer - germinal epithelium

• deep to that is the tunic albuginea (dense CT)

• outer cortex + inner medulla

• ovarium artery and vein

• tissue

  • ovarian ligament

  • mesovarium

  • broad ligament

  • suspensory ligament

ovarian follicles

• site of oocyte production and sex hormone release

• consist of oocyte surrounded by follicle cell

  • support the oocyte

  • thousands found in the cortex

  • 6 main types

ovarian artery and ovarian vein

• supply each ovary

• ovarian arteries are direct branches off the aorta

• veins drain into the inferior vena cava or renal vein

innervation of the reproductive system

• autonomic nervous system

  • sympathetic: T10 segments of the spinal cord

  • parasympathetic: CN X

6 types of follicles

1.) primordial follicles

2.) primary

3.) secondary

4.) antral

5.) mature

6.) oocyte

follicle steps

primordial -- primary -- secondary -- antral -- mature -- oocyte

primary follicle

• granulosa cells

• secretes estrogen and it matures

  • stimulates change in the uterine lining

• zona pellucida: translucent structure containing glycoproteins

• cuboidal epithelium

secondary follicle

• layers of granulosa cells + thecal cells

• helps control development and secretes androgen

antral follicle

• many layers of granulosa cells and fluid-filled space (antrum)

• serous fluid lets oocyte be able to leave unscathed

mature follicle

• form from a secondary follicle

• bigger and more fluid

• one formed per month

• contains a secondary oocyte

• the oocyte is released

corpus luteum

• forms from remnants of follicle

• after mature follicle ruptures and oocyte expelled

• secretes progesterone and estrogen

• 1st step of reabsorbing follicle tissue

corpus albicans

• formed from regressed corpus luteum

• white CT scar -- also reabsorbed

• most structures are reabsorbed

primordial follicle

• most primitive type of ovarian follicle

• primary oocyte and a single flattened layer of follicle cells

• 1.5 million presented at birth

thecal cells

• help control follicle development

• secrete androgens are converted to estrogen by granulosa cells

before birth (oogenesis)

oogonia

childhood oogensis

atresia

menopause

• woman cease cycling for 1 year

• not pregnant or have other medical condition

• normal onset about 45-55 yr/old

oogenesis

maturation of a primary oocyte to a secondary oocyte

before birth follicle development

primordial follicle

puberty to menopause follicle development

• primary follicle

• secondary follicle

• antral follicle

• mature follicle

• outdated seconday oocyte

• corpus luteum

• corpus albicans

ovarian cycle phases

• follicular phase

• ovulation

• luteal phase

• menarche (menstral cycle)

follicular phase

• days 1-13

• stimulated by LH and FSH

• granulosa cells release inhibin = increase FSH because we want more follicles

• oocye forced to one side of follicle

• polar body formed

ovulation

• release of a secondary oocyte from a mature follicle

• occurs on day 14

• peak LH secretion

  • follicle continues to expand and the surface becomes really thin

luteal phase

• days 15-28

• remaining follicle cells become corpus luteum

• causes menstruation (marks the end of the luteal phase)

ovarian cancer

• primary malignancy in the ovary

• may originate from oocytes, CT, or surface epithelium

• 5th most common cancer in women

• initial symptoms are non-specific

  • constipation, urinary urgency, abdominal swelling, pelvic pain, indigestion, nausea, back pain, weight changes

• no reliable test for disease

• often detected late

• treatment: surgery or chemotherapy

HCG

human chorionic gonadotropin

uterine tubes

• infundibulum

• ampula

• isthmus

• intra-mural (uterine body)

HSG

ink can be inserted into the uterus/vagina to release ink to see if the tubes are blocked

uterine tubes function

transport

what section of the uterine tube does fertilization occur?

ampulla

ectopic pregnancy

fertilized oocyte implants outside the endometrium

tubal pregnancy

• one type of ectopic pregnancy

• fertilize egg implants in the uterine tube

• unable to expand as the embryo grows

• embyro only viable until week 8

• uterine wall ruptures if the embryo is not removed

• hemorrhage and loss of life possible

3 tunics of the uterus

• mucosa (simple ciliated columnar epithelium)

• muscularis (circular and longitudinal)

• serosa

shape and location of the uterus

• pear shaped

• lumen area

• anteverted (pointing toward the belly button)

function of the uterus

• site for pre-embryo

• supports, protects, nourishes the developing embryo

• ejects fetus at birth (baroreceptors + positive feedback)

regions of the uterus

• fundus

• body

• isthmus

• cervix

endometriosis

• part of the endometrium is displaced

  • the tissue becomes implanted on the external surface of organs within the abdominopelvic cavity

• may be grown under the influence of hormones

  • cannot be expelled normally

  • may cause pain and scarring

  • often linked to fertility problems

treatment for endometriosis

• hormones to retard the growth of endometrial tissue

• surgery

uterine cycle

• menstrual phase

• proliferative phase

• secretory phase

menstrual phase

• day 1-5 of cycle

• ditching the functional layer of endometrium

proliferative phase

• days 6-14 of the cycle

• making a new functional layer

secretory phase

• days 15-28 of the cycle

• increased vascularization and development of uterine glands = a response to progesterone from corpus luteum

when ovulation approaches…

• granulosa cells of the mature follicle increase their rate of fluid secretion into the antrum

• the volume then increases and the edge of the follcicle becomes thin and eventaully reptures

• this expells the secondary oocyte through the mature follicle and the ovary wall in hope of fertilization

cervical cancer

common malignancy of the female reproductive system

most important risk factor of cervical cancer

• human papillomavirus (HPV)

  • vaccine available for 4 most common types

pap smear

• detects cervical cancer in early stage

• epithelial cells scraped from the cervix edge

• examined for abnormal development

• if cancerous cells are present, a portion of the cervix is removed

  • if invasive the uterus is removed (hysterectomy)

vagina

• fibromuscular tube

• 3 tunics

  • mucosa

    • nonkeratinized stratified squamous epithelium

    • highly vascularized and acidic

  • muscularis

    • 2 layers of smooth muscle

  • adventitia

    • inner elastic fiber

    • outer layer of areolar CT

vagina function

birth, penis, and menstruation canal

vulva components

• mons pubis

• labia majora

• labia minora

• vestibule

• bulb of the vestible (clit)

• greater vestibular glands

clitoris

• body, crus, glans

• 2 erectile bodies

mammary gland

• each is located within the anterior thoracic wall

• composed of the tubuloalveolar exocrine gland

• secretory product = breast milk

  • proteins, fats, and lactose sugar for infant nutrition

mammary gland 3 hormones/processes

• lactation

• prolactin

• oxytocin

lactation

• release of breast milk

• occurs in response to internal and external stimuli

• start to produce after giving birth

prolactin

• produced in the anterior pituitary and responsible for milk production

• with the increase, the mammary gland forms more and larger alveoli

oxytocin

• produced by the hypothalamus and released from the posterior pituitary

• responsible for milk ejection

breast cancer

• occurs in 1 in 8 women in the U.S

• risk factors

  • family history, longer reproductive span, obesity, nulliparity, late age at first pregnancy, specific genes (BRCA1 and BRCA2)

male primary reproductive organs

testes

male accessory reproductive organs

• ducts and tubules leading from the testes to the penis

• male accessory glands

• penis

the cremaster muscle and dartos muscle are responsible for…

lifting and letting down the testes in response to changes in temperature

scrotum

responses to temperature changes

elevated temperature - scrotum response

• relaxation of the dartos muscle

• testes move inferiorly + cools testes

• cremaster muscle relaxes to allow testes to move inferiorly

decreased temperature - scrotum response

• contraction of dartos and cremaster muscle

• testes and scrotum pulled closer to body

• helps conserve heat

testes + spermatogenesis

• relatively small organs housed within the scrotum

• produces sperm and androgens

• covered anteriorly and laterally by a serous membrane

• outer pariteal and visceral layer

• endocrine cascade along the testes

seminiferous tubules

• 4 of them per lobule

• extremely convoluted

• release inhibin when sperm count is high

• FSH increases oocyte and sperm production

• contain dividing germ cells continuously producing sperm

blood testes barrier

protects sperm from the body’s defenses

defense for sperm

• scrotum

  • temperature regulation

• blood barrier

• interstitial spaces

• interstitial cells

spermatogonia

• all sperm develop primordial germ cells

  • primary

  • secondary spermatid

spermiogenesis

• final stage of spermatogenesis

• becomes mature sperm

• acrosome cap to protect DNA

• needs to be digestive enzymes, motile and fast

spermatid

mature sperm

sperm development

• golgi phase

• cap phase

• tail phase

• mid piece (mitochondria phase)

male vs. female gametogenesis

female

• oocytes arrested in mieosis before birth

• able to produce until menopause

• single viable secondary oocyte produced in females

male

• produce throughout life

• 4 sperms in males

duct system

• R and L testes each have their own set of ducts

• ciliated columnar and non-ciliated colmnar

• transport and store sperm as they mature

  • rete testis

  • efferent ductules

  • epididymis

  • ductus deferens

  • ejaculatory duct

urethra

transports semen from ejactulatory ducts to outside of body

• prostatic urethra

• membranous urethra

• spongy urethra

epididymis

comma shaped duct that loops back into the testes

epididymis _____ sperm

store

testes _____ sperm

make

ductus deferens

• sperm enter after leaving epididymis

• long transport system

• muscular wall composition

  • 3 layers of smooth muscle

  • contractions aid movements

• pseudostratified ciliated columnar epithelium

• outer adventitia

seminal fluid

• 3 accessory glands

• alkaline environment

seminal fluid is produced by…

produced by seminal vesicles, prostate gland, and bulbourethral glands

semen

• formed from seminal fluid and sperm

• 200 to 500 million spermatozoa

• transit time from seminiferous tubules to ejaculate is about 2 weeks

semen is also called ____ during _____

ejaculate, intercourse

benign prostatic hyperplasia

non-cancerous enlargement of the prostate gland

• common in older men

• due to hormonal changes in aging males

• large nodules forming within the prostate and compressing the urethra

treatment for benign prostatic hyperplasia

• can be treated with drugs

• may require surgical removal of prostatic enlargement

symptoms of benign prostatic hyperplasia

• frequent urinating at night

• frequent and painful urination

prostate cancer

one of the most common malignancies in men over 50

• forms hard, solid nodules within the prostate

• asymptomatic early on, later urinary symptoms

• screening with digital rectal exam + PSA test

treatment for prostate cancer

radiation therapy or surgical removal

penis

forms external genitalia with scrotum

• root

• body

• glans

• prepuce (foreskin)

sexual response

• desire (libido)

• arousal (excitement)

• orgasm

• resolution

men have a _______ period during sexual response

refractory

birth control

• plan A

  • birth control (reversible + irreversible)

• plan b

  • emergency contraceptive

• plan c

  • abortion (chemical or medical)