Histology of Female Reproductive System II

Question 1

What is the uterine tube and its function?

Answer 1

Fallopian tube

Structure maintains the oocyte and facilitate its movement on its journey toward the uterus

Is the normal site of fertilization

Question 2

What are the parts of the uterine tube?

Answer 2

Infundibulum - has fimbriae, free end opens into the peritoneal cavity. Fimbriae facilitate capture of the oocyte at ovulation so that it can pass into the lumen of the tube

Ampulla - dilated portion of tube, about 2/3rd of tube’s length, longest and widest part, site of fertilization

Isthmus - constricted connected to uterus

Uterine (intramural) part - extends into uterine wall

Question 3

What are the layers of the uterine tube?

Answer 3

Mucosa - longitudinal folds that increase surface area

Muscularis - smooth muscle

Serosa - mesosalpinx which invests the uterine tube

Question 4

Describe the mucosa of the uterine tube

Answer 4

Has longitudinal folds

Epithelium is simple columnar:

Ciliated cells create brush like surface and sweep oocyte towards uterus

Nonciliated peg cells - produce nutrient rich protective secretions for oocyte, sperm, or zygote

Lamina propria - loose CT

Question 5

Describe the muscularis of the uterine tube

Answer 5

Thick layer of inner circular fibers

Thin layer of outer longitudinal fibers

Produces rhythmic peristaltic waves that facilitate the movement of the oocyte from the infundibulum to the ampulla (and toward uterus)

Question 6

Describe the serosa of the uterine tube

Answer 6

Mesosalpinx which invests the uterine tube

Visceral peritoneum (mesothelium and thin layer of CT)

Question 7

What is the function of the uterus?

Answer 7

Site of implantation of the blastocyst

Protects and nurture the developing embryo and fetus during the 9 month gestation

Question 8

What are the layers of the uterus?

Answer 8

Endometrium - mucosa

Myometrium - smooth muscle

Perimetrium - outer layer

Cervix - lower cylindrical part of uterus, connects uterus to the vagina

Question 9

Describe the endometrium of uterus

Answer 9

Epithelium - simple columnar with ciliated cells and nonciliated secretory cells (secrete glycoproteins)

Lamina propria - simple branched tubular glands (uterine glands), fibroblasts, dense irregular collagenous CT

Question 10

What are in the lamina propria of the endometrium?

Answer 10

Stratum functionale - sloughed off in menstruation and in pregnant women, it is reffered to as decidua

Stratum basale - remains to repave the functional layer

Blood vessels - uterine artery gives rise to arcuate arteries - radial arteries also present

Question 11

What is endometriosis?

Answer 11

Endometrial tissue growing in the pelvis or peritoneal cavity

Origin of tissue is unknown

Extrauterine endometrial tissue may undergo cyclical changes like intrauterine endometrial tissue - hemorrhaging of this tissue may cause adhesions and pain - predominant cause of infertility in reproductive age females

Question 12

What are the three hypotheses for origin of endometrial tissue in pelvis or peritoneal cavity in endometriosis?

Answer 12

1. Regurgitation hypothesis - menstrual flow escapes from uterus via the uterine tubes to enter the peritoneal cavity
2. Metaplastic hypothesis - epithelial cells of the peritoneum differentiate into endometrial cells
3. Vascular dissemination hypothesis - endometrial cells enter vascular channels during menstruation and are distributed by the blood or lymph system

Question 13

Describe the myometrium of the uterus

Answer 13

Smooth muscle

Inner longitudinal layer

Middle circular layers with larger blood vessels

Outer longitudinal layer

During pregnancy, the smooth muscle cells of the myometrium undergo hypertrophy (increase in cell size) and hyperplasty (increase in cells numbers via mitotic division)

Question 14

Describe the perimetrium of the uterus

Answer 14

Serosa - mesothelium and loose CT

Adventitia - CT which attaches to surrounding structures

Question 15

Describe the cervix of the uterus

Answer 15

Lining is made of mucous secreting simple columnar epithelium

85% tough fibrous dense CT, elastic fibers, some smooth muscle

Vaginal part (ectocervix) - stratified squamous nonkertatinizing epith

Mucosa - cervical glands are branched and numerous. Nabothian cysts result from secretions obstructing the ducts of the cervical glands

Ovarian hormones influences the amount and consistency of the mucus released by cervical glands

Question 16

What is the menstrual cycle?

Answer 16

In response to estrogen and progesterone released by the ovary, the endometrium undergoes structural changes during the 28 day menstrual cycle to prepare for implantation of blastocyst

If there is no implantation, a layer of endometrium (stratum functionale) degenerates, sloughs off, and menstrual bleeding occurs

Question 17

What occurs during the menstrual phase of the menstrual cycle?

Answer 17

Days 1-4

If fertilization/implantation does not occur, CL stops functioning in about 14 days

PG and estrogen levels decline

Smooth muscle in wall of spiral arteries contract

Blood flow to functional layer decrease

Functional layer becomes ischemic and blood flow to endometrial lining ceases

Necrosis of functional layer

Blood vessels break off and functional layer of endometrium sloughs off

Bleeding occurs and blood and functional layer are released

Question 18

What occurs during the proliferative phase of the menstrual cycle? What are the other names for this cycle?

Answer 18

Follicular and estrogenic phase

Days 5-14

Uterine mucosa - lamina propria with basal portions of the glands

Estrogen stimulates proliferation of epithelium, glands, vessels

Glands consist of straight tubules lined with simple columnar epithelium

Spiral arteries grow into the repaved endometrial stroma

Question 19

What occurs during the secretory phase of the menstrual cycle? What are the other names for this phase?

Answer 19

Luteal and progestational phase

Days 15-28

Starts after ovulation

PG stimulates glands to synthesize and release glycoproteins, whcih may nourish the implanted blastocyst

Glands become coiled

Spiral arteries grow into the functional layer of endometrium

Question 20

What are uterine leiomyomas (fibroids)?

Answer 20

Most common benign neoplasms of smooth muscle origin in women

Occur as a single tumor, but usually occur as multiple, distinct tumors

40% of sufferers have some chromosomal abnormality

When large and multiple they may cause abnormally heavy menstrual periods

Large leiomyomas may compress the urinary bladder, causing frequent urination

During pregnancy they increase miscarriage and postpartum hemorrhage

Question 21

What are the locations and morphology of uterine fibroids?

Answer 21

Locations:
Intramural - in myometrium
Submucosal - deep to uterine mucosa
Subserosal - deep to serosa

Morphology - well define and spherical, firm, gray, or white growth. Size varies and have whorled appearance

Question 22

What are the layers of the vagina?

Answer 22

Mucosa

Muscular layer

Adventitia

Question 23

What is the structure of the mucosa of the vagina?

Answer 23

Epithelium - stratified squamous nonkeratinizing epithelium, glycogen

Lamina propria - abundant elastic fibers, loose fibroelastic CT, lymphoctyes, neutrophils, no glands

Question 24

What is the muscular layer of the vagina?

Answer 24

Thin inner layer, circular smooth muscle fibers

Thicker outer layer, longitudinal fibers, continuous with corresponding uterine layer

Question 25

What is the adventitia of the vagina?

Answer 25

Dense connective tissue

Thick elastic fibers

Venous plexus

Nerve bundles

Question 26

What are the mammary glands composed of?

Answer 26

Compound tubuloalveolar glands

Resting (non-lactating) mammary gland

Lactating (active) mammary gland - alveoli