histo repro (p1)

reproductive system

The only organ system where there are glaring anatomic differences between male and female. •

male gamete

sperm cell, spermatozoon

female gamete

egg cell (ovum)

testes, genital ducts, accessory glands, and penis

The male reproductive system consists of the

testes

produce sperm but also contain endocrine cells secreting hormones such as testosterone, which drives male reproductive physiology.

Dihydrotestosterone

metabolite of testosterone _ , also begins to act on many tissues during puberty (eg, male accessory glands and hair follicles)

mediastinum testis

TA thickens on the posterior side to form the

houses rete testis

testicular lobules

fibrous region, septa penetrate the organ and divide it into about 250 pyramidal compartment forming

tunica albuginea

dense connective tissue capsule surrounding the testis

leydig cells

endocrine interstitial cells

secrete testosterone

seminiferous tubules

site of sperm production

tunica vaginalis

each testis carries with it a serous sac, the tunica ___, derived from the peritoneum

34°c

A permissive temperature of about ___ is maintained in the scrotal sac by various mechanisms.

pampiniform plexus

Surrounds each testicular artery

▪ contains cooler blood from the testis, which draws heat from the arterial blood by a countercurrent heat exchange system.

dartos muscle

cremaster muscle

Relaxation or contraction of the thin ____ of the scrotum and the ____ of the spermatic cords move the testes away from or closer to the body, respectively, allowing further control on testicular temperature.

hydrocele

An excessive accumulation of serous fluid in one or both sides of the scrotal sac, termed a ____ , is the most common cause of scrotal swelling and a condition easily corrected surgically

cryptorchidism

the failure of one or both testes to descend from the abdomen, occurs in about 4% of male neonates, but in most of these individuals the testes move to the scrotum during the first year

interstitial tissue / leydig cells

between the seminiferous tubules consists of sparse connective tissue containing fibroblasts, lymphatics, and blood vessels including fenestrated capillaries.

• During puberty, develop as large round or polygonal cells with central nuclei and eosinophilic cytoplasm rich in small lipid droplets

luteinizing hormone

interstitial cell stimulating hormone

Testosterone secretion by interstitial cells is triggered by the pituitary gonadotropin, ___, which is also called ____

➢ Testosterone synthesis thus begins at puberty

seminiferous tubules

Produces Sperm at a rate of about 2 × 108 per day in the young adult.

straight tubule

rete testis

Each tubule is actually a loop linked by a very short, narrower segment, the ___, to the ___

rete testis

a labyrinth of epithelium-lined channels embedded in the mediastinum testis

• About 10-20 efferent ductules connect the ___ to the head of the epididymis

Germinal (spermatogenic) epithelium

Each seminiferous tubule is lined with a complex, specialized stratified epithelium called

myoid cells

The basement membrane of this epithelium is covered by smooth muscle-like ___ which allow weak contractions of the tubule.

Spermatogenesis

spermiogenesis

sperm production

spermatogenesis

the first part of sperm production involves mainly mitosis and meiosis

spermatogonia

spermatogenic progenitor cells, called ____, are diploid cells containing 46 chromosomes (23 pairs).

primary spermatocytes

Mitotic divisions of these cells produce new spermatogonia and cells called _____ which are committed to meiosis

2 haploid secondary spermatocytes

cells replicate their DNA, enter meiosis I. The first meiotic division produces ____ each with 23 chromosomes

spermatids

separate into two smaller haploid cells, the ___

Sperm

spermatids differentiate and undergo the morphological changes required to become motile and capable of fertilization

Spermiogenesis

final phase of sperm production

• the temperature-sensitive process by which spermatids differentiate into spermatozoa, which are highly specialized to deliver male DNA to the ovum.

golgi phase

cap

maturation

​

phases of spermiogenesis

spermiation

process by which mature spermatids are released from Sertoli cells into the seminiferous tubule lumen prior to their passage to the epididymis

straight ductule

rete testis

efferent ductules

intratesticular ducts

epididymis

urethra

ductus or vas deferens

excretory genital ducts

epididymis

Nearly 6 m in length

• Head - region where the efferent ductules enter

• Body - where sperm cells undergo further subtle modifications

• Tail - where sperm are stored until ejaculation

accessory glands

produce secretions, which become mixed with sperm during ejaculation to produce semen and are essential for reproduction.

seminal vesicles

prostate glands

bulbourethral glands

accessory glands

seminal vesicles

prostate glands

produce major volume to semen

fructose

prostaglandin

fibrinogen

secretion of seminal vesicles

fructose

fructose

major energy source for sperm, as well as inositol, citrate, and other metabolites

prostaglandin

stimulate activity in the female reproductive tract

fibrinogen

allows semen to coagulate after ejaculation

prostate gland

2 cm × 3 cm × 4 cm in size and weighs about 20 g

dense organ that surrounds the urethra below the bladder.

bulbourethral glands (Cowper's glands)

3-5 mm in diameter, are located in the urogenital diaphragm

• lubricates the urethra in preparation for the imminent passage of sperm

transition

central

peripheral

3 transition zones of the urethra

transition zine

5% of the prostate volume

• surrounds the superior portion of the urethra

• contains the periurethral mucosal glands

central zone

25% of the gland's tissue

• contains the periurethral submucosal glands

peripheral zone

70% of the organ's tissue

• contains the prostate's main glands

chronic prostatitis

nodular hyperplasia / benign prostatic hypertrophy

prostate cancer

common problems of prostate glands

nodular hyperplasia

occurring mainly in the periurethral mucosal glands where it often leads to compression of the urethra and problems with urination

penis

consists of three cylindrical masses of erectile tissue, plus the penile urethra, surrounded by skin 1. Two of the erectile masses—the corpora cavernosa—are dorsal;

2. the ventral corpus spongiosum surrounds the urethra

- At its end the corpus spongiosum expands, forming the glans

corpora cavernosa

corpus spongiosum

2 erectile masses

- dorsal

- ventral, surrounds urethra

acetylcholine

parasympathetic

helicine

nitric oxide

guanylate cyclase

cyclic GMP

relax

at the beginning of an erection ___ from ___ nerves in the penis causes the vascular endothelial cells of the ____ arteries and cavernous tissue to release ____. Diffusing into the adjacent smooth muscle cells, NO activates _____ to produce _____, which causes these cells to ____, resulting in increased blood flow, filling of the cavernous spaces, and penile erection.

cortex of ovary

medulla of ovary

region with a stroma of highly cellular connective tissue and many ovarian follicles

-the most internal part of the ovary contains loose connective tissue and blood vessels entering the organ

primordial germ cell

oogonia

- _____ migrates from the yolk sac to the gonadal primordia. -undergo synchronized mitotic divisions with incomplete cytokinesis, producing a few million interconnected ____

11-12 weeks of gestation

mitosis stops

prophase

primary oocytes

follicular

clustered oogonia enter the long ___ of a first meiotic division

-cells in meiotic arrest are called ____ surrounded by flattened support cells called ____ cells to form a non-growing follicle.

ovarian reserve

follicular atresia

birth there are about 680,000 such follicles, sometimes called the "____," of which about 460,000 remain at puberty, the others having been lost through the degenerative process called ____, which only ends with menopause

Unilaminar primary follicles

Follicular cells undergo mitosis and form a simple cuboidal epithelium around the growing oocyte =

stratified follicular epithelium

granulosa cells

inhibin

multilaminar primary follicle

The follicular cells continue to proliferate, forming a ____, the ___ cells, (secretes hormone ____) in which the cells communicate through gap junctions =

Androstenedione

aromatase

estradiol

____ (produced by Theca interna), precursor molecule diffuses into the follicle through the basement membrane, and in the granulosa cells the enzyme ___ converts it to ___, an FSH-dependent function.

estrogen

This ___ returns to the thecae and stroma around the follicle, enters capillaries, and is distributed throughout the body, inducing the changes characteristic of puberty.

follicular fluid

antrum

secondary or antral follicles

Within such follicles small spaces appear between the granulosa layers as the cells secrete____(or liquor folliculi). Granulosa cells reorganize themselves around a larger cavity called the ___ producing follicles now called ____ or ___ follicles.

graafian

corona radiata

single large antrum of a mature or ___ follicle rapidly accumulates more follicular fluid and expands to a diameter of 2 cm. The tightly adhering granulosa cells immediately surrounding the zona pellucida make up the ___ and accompany the oocyte when it leaves the ovary at ovulation.

trophoblast

human chorionic gonadotropin

To prevent the drop in circulating progesterone, ____ cells of the implanted embryo produce a glycoprotein hormone called ____.

infundibulum

ampulla

isthmus

uterine or intramural part

Uterine tube can be divided into 4 segments by gross inspection

infundibulum

funnel-shaped opening fringed with fingerlike extensions called fimbriae next to the ovary

ampulla

the longest and expanded region where fertilization normally occurs

isthmus

a more narrow portion nearer the uterus;

uterine or intramural part

which passes through the wall of the uterus and opens into the interior of this organ.

salpingitis

uterine tube mucosa can become inflamed if infectious agents ascend from the lower genital tract. Mucosal damage or adhesions caused by chronic salpingitis can lead to infertility

uterus

pear-shaped organ with thick, muscular walls

• largest part, the body, is entered by the left and right uterine tubes

fundus

isthmus

curved superior area between the tubes is called the ___

• narrows in the ___

• ends in a lower cylindrical structure, the cervix.

• lumen of the cervix, the cervical canal, has constricted openings at each end:

menstrual period

follicular, estrogenic, proliferative

secretory, luteal

_____ lasts 3-4 days on average.

2. ____ phase/ ____ or ___ phase is of variable length, 8-10 days on average,

3. ___ phase/ ___ phase begins at ovulation and lasts about 14 day

decidual cell

decidua

The endometrial stroma undergoes histologic changes in the period following implantation ➔___

. The whole endometrium is now called ___

decidua basalis

decidua capsularis

decidua parietalis

____, the area between the implanted embryo and the myometrium;

2. ___, the region between the embryo and the uterine lumen that thins as the embryo gets larger

3. ____, on the side of the uterus away from the embryo

chorion

embryonic part, derived from the trophoblast

✓ maternal part is from the decidua basalis

placenta

site of exchange for nutrients, wastes, O 2 , and CO 2 between the mother and the fetus and contains tissues from both individuals.

primary

secondary

tertiary villi

Chorionic villi of the developing placenta go through three stages

primary villi

secondary villi

tertiary villi

___ appear 2 days after implantation as simple cords of proliferating cytotrophoblast cells 2. ____ begin to form on about the 15th day of embryonic development

3. ____ develop within a few more days as mesenchyme in the secondary villi differentiates to form capillary loops continuous with the embryonic circulatory system.

transformation zone

The junction between this squamous epithelium and the mucus-secreting columnar epithelium of the endocervix occurs in the ___, an area just outside the external os that shifts slightly with the cyclical changes in uterine size

vagina

wall lacks glands and consists:

1. mucosa

2. muscular layer

3. adventitia. lamina propria nonkeratinized stratified squamous epithelium (E) muscular layer

• thickness of 150-200 μm in adults Stimulated by estrogens, the epithelial cells synthesize and accumulate glycogen. glycogen (in desquamated cells) + bacteria

➔ Lactic acid (low pH within the vagina

vulva

or external genitalia

vestibule

space whose wall includes the tubuloacinar vestibular glands;

labia minora

The paired ___, folds of skin lacking hair follicles but with numerous sebaceous glands;

labia majora

The paired ____, homologous and histologically similar to the skin of the scrotum; and

clitoris

an erectile structure homologous to the penis with paired corpora cavernosa.

mammary glands

develop embryologically as invaginations of surface ectoderm • one set of glands resembling highly modified apocrine sweat glands persists on each side of the chest

• Each gland consists of 15-25 compound tubuloalveolar lobes

• The histologic structure of the mammary glands varies according to sex, age, and physiologic status.

areola

skin surrounding nipple, contains sebaceous glands and abundant sensory nerves and is continuous with the mucosa of the lactiferous sinuses

nipple

15-25pore-like openings, each about 0.5 mm in diameter. Connected to a compound tubuloalveolar lobes

late pregnancy

colostrum

prolactin

the glandular alveoli and ducts are dilated by an accumulation of ____, a fluid rich in proteins and containing leukocytes, which is produced under the influence of ____

Following parturition

lactation

prolactin

____, the alveoli of mammary glands start active milk production, or ____, stimulated primarily by ___ from the anterior pituitary

Oxytocin (from hypothalamus)

-contraction of the smooth muscle of the lactiferous sinuses and ducts, as well as the myoepithelial cells of alveoli and ducts, resulting in the milk-ejection reflex/Let-down reflex.

lipid droplets

lactose

human milk. contain

lipid droplets

form initially from short-chain fatty acids synthesized in the epithelial cells

➔ apocrine secretion

lactose

the major carbohydrate and energy source in milk, is synthesized in the Golgi apparatus and secreted with lactalbumin

breast cancer

almost always derived from epithelial cells in the terminal lobules of the glands.