Biology 2404 A&P Basics

The ovaries are paired oval structures inferior to the kidneys in the mid abdominal region and are suspended by suspensory, ovarian, and broad ligaments. The ovaries are covered by a connective tissue called the tunica albuginea that forms an outer capsule. The ovarian cortex contains ovarian follicles consists of developing immature eggs (oocytes) and surrounding cuboidal cells, thecal cells. In each follicle, the immature eggs undergo oogenesis triggered by the hormones secreted by the thecal cells.

Primordial follicles oogonia precursor cell

Primary follicles primary oocytes haploid cells, meiosis I

Secondary follicles secondary oocytes haploid cells, meiosis II

Tertiary, Graafian follicles secondary oocytes haploid cells, meiosis II

Atretic follicles deteriorating oocytes no function

Ovarian Model

Meiosis Wall Mount

Ovarian Histology Drawing

Ovarian Histology: primordial, follicles [primary, secondary, tertiary], CL

Ovarian Hormones and Cycle

The hormones from the thecal cells that line the follicles are:

DHEA is a hormone precursor to other reproductive hormones that control the ovarian and uterine cycles.

Estrogens estradial, estrone

Progestins progesterone

Androgens testosterone

Estrogens also function in creating secondary sex characteristics: Fat deposition, breast development, hair distribution, skin changes, and bone development

Hormonal control of the ovaries begins in the Hypothalamus with GnRH release triggering response of the AP to release either FSH or LH.

GnRH for FSH ovarian thecal cells reproductive hormones, primarily estrogens

GnRH for LH affects tertiary follicles to causeovulation of secondary oocyte

while the remaining thecal cells form the corpus luteum

In summary, the function of the ovaries is to produce gametes in a process called oogeneis and to produce reproductive hormones in response to homeostatic feedback signals. Hormones control oogenesis and uterine lining changes.

The ovarian cycle is named for the events triggered by hormone response.

Follicular Phase ovarian follicles develop from primordial to Graafian

triggered by estrogen production

Ovulation Graafian follicle ruptures to release secondary oocyte

triggered by AP – LH

Luteal formation of corpus luteum (CL) from leftover thecal cells

function to secrete progestins and estrogens

triggered by LH

Female reproductive Model

Female reproductive wall mount

Duct System

The Fallopian tubes (Salphinx, Uterine Tubes, Oviducts) develop separately from the ovaries. At the lateral end of the tube, there are finger like extensions called fimbria that function to create vacuum like currents to retrieve the ovulated secondary oocytes.

The fimbria is supported by an enlarged trumpet shaped base called the infundibulum.

The infundibulum continues as the expanded portion of the tube called the ampulla and it is where fertilization takes place. As the tube continues, its medial end is attached to the uterus at the isthmus. In summary, the function of the Fallopian tube is in oocyte transport and fertilization.

The uterus is a pear shaped structure in the pelvic region of the abdominal cavity suspended by the broad ligament. The external anatomy consists of the fundus, body, and neck or cervix. The internal anatomy of the uterus is composed of three layers. The internal epithelial lining is the endometrium and is a modified simple columnar epithelium in two layers, the basilar layer and the functional layer. The muscle wall is the myometrium and is composed of smooth muscle. The outer layer is a connective tissue layer called the perimetrium formed by the visceral peritoneum.

The uterus can change size and shape during pregnancy. The lining of the uterus will undergo several cycles known as the uterine cycle and relates to the hormones produced during the ovarian cycle. The function of the uterus is to provide protection, support, and nutrition to the developing fetus and aid in delivery during labor.

Proliferation (pre ovulatory) basilar layer of endometrium replaces functional layer

triggered by estrogens from the ovary

Secretory (post ovulatory) functional layer secretes nutrients for fertilized egg

triggered by progestins and estrogens from the ovary

Menstrual (post luteal) functional layer of endometrium lost

triggered by a dramatic drop in ovarian hormones

The vagina is a muscular tube that connects the cervix of the uterus at the fornix. The vagina functions as the female organ of copulation, serve as pathway for menstrual flow, and the birth canal. The vaginal lining is stratified squamous and has an acidic pH to prevent overgrowth of bacteria. A thin fold of tissue called the hymen partially closes the distal end of the vagina. The vaginal orifice is the opening of the vagina in the vestibule enclosed by the labia.

Female reproductive models

Large

Small

Superior View

Inferior View

Female reproductive wall mount

Ovarian and Fallopian tube histology

Uterus histology: Proliferative, Premenstrual

Vaginal histology

External Genitalia

External Genitalia of the female is collectively termed the vulva or pudendum.

The vulva is comprised of the:

clitoris erectile tissue composed of corpora spongiosum

labia majora analogous to the male scrotum, contains sweat glands

labia minora smaller skin fold that contains sebaceous glands

both labia cover the vagina and urethra to help prevent drying

mons pubis fat over the pelvic symphysis, covered by skin and pubic hair

Female Models : Large, Small

Female Wall Mount

Vulva Model

Accessory Glands

Accessory Organs of the female consist of the:

Lesser vestibular glands, Skene’s glands on either side of the urethral oriface. They are analogous to the male prostate gland and secrete mucus for vaginal lubrication.

Greater vestibular glands, Bartholin’s glands on either side of the vaginal orifice. They are analogous to the male Cowper’s glands and secrete mucus for vaginal lubrication.

Mammary glands modified sweat glands of the skin that is functional in females

produce milk in response to AP – Prolactin (PRL) hormone

Lactiferous glands are surrounded by fat and supported by

ligaments that anchor the breast tissue to the pectoral muscles

of the chest.

Milk glandular alveoli develop in response to estrogens.

Milk release is under the control of the PP – Oxytocin (OT)

and will travel through lactiferous ducts to the lactiferous sinus and exit at the nipple surrounded by pigmented skin, theareola.

Female body torso

Female Lower pelvis with Urinary System

Mammary Histology: Active, Inactive, Nipple

Problems: Female Reproductive system

Medical Terminology

-ac pertaining to -algia pain

gyne, gyn/o- women hyster/o- uterus

lapar/o- loin mammilla- breast

mast/o- breast o, oo- egg

-(r)rhea flow, discharge salphing/o- tube

lute- yellow mens- month

ova- egg vagin/o- sheath

cervic/o- cervix colp/o- vagina

episi/o-, vulv/o- vulva galact/o-, lact/o- milk

gynec/o- female uter/o-, metr/o- uterus

labi/o- lip-like oophor/o, ovari/o ovary

ob- against spor- seed

Exercises/Activities

I. ID female reproductive organs

A Drawing

B Models

C Wall mount

II. Hormone levels in cycles

Concept Map: Make a concept map of the female reproductive system (gross and histo) anatomy, location, and physiological function. Include hormones, source, target, effects. This concept map should be sent as part of the LAR lab report (if selected) as a document insert or as an additional PDF scanned document.

Case Study

Applications

Endometriosis

Uterine Leiomyomas

Fibroids

Mastitis

Uterine Polyps

Ovarian Cysts

Ovarian Cancer

Menorrhagia

Sexually Transmitted Disease (STD)

Gonorrhea, Syphilis, Genital Herpes, Chlamydia, Trichomoniasis, Genital Warts