Female Reproductive System
Female Reproductive System
Objectives
· Identify the internal and external organs of the female reproduction system and their features
· Describe lactation and identify the structures of the mammary glands
· Describe the phases of the menstrual cycle
· Describe the movement of an egg from the ovary to the external environment
Female Reproductive Anatomy
[Section 27.2: Anatomy and Physiology of the Female Reproductive System]
The female reproductive system includes both internal and external organs
Collectively, they function to:
· Produce the female gamete
· Receive male gametes
· Transports oocytes
· Protect and nourish developing embryo
· Deliver child
External Organs
Vulva
[Section 27.2.1: External Female Genitals]
[Figure 27.9: Female Reproductive System; Figure 27.10: The Vulva]
“Vulva” is the collective term for the external female genitalia.
They consist of:
· Mons pubis: fatty pad that cushions and protects pubic symphysis during sexual intercourse
· Labia majora: two fatty folds that extend posteriorly from the mons pubis; homologous to the male scrotum; contain pubic hair, sudoriferous and sebaceous glands
· Labia minora- two smaller parallel folds, contain sebaceous glands but no hair, covers clitoris
· Clitoris- made of highly sensitive erectile tissue (same embryonic tissue that forms male penis), exposed region is called the glans
· Vestibule- between labia minora, contains vaginal orifice, hymen, the external urethra orifice (which has no reproductive function) and greater vestibular glands (secrete lubricant)
Internal Organs
Vagina
[Figure 27.9: Female Reproductive System; Figure 27.10: The Vulva]
· Female copulatory organ
· Birth canal
· Lined with stratified squamous epithelium in order to handle “abrasion” during childbirth or intercourse
· Passageway for menstruation
· Approximately 10 cm (4 in) long
· The vaginal orifice is the external opening of the vagina (occluded by the hymen)
Ovaries
· The primary reproductive organ of females
· Produce endocrine (estrogen and progesterone) and exocrine (eggs, or ova) products
· Supported by the ovarian ligament, the suspensory ligaments and the mesovarium.
· Houses the female gametes (eggs) in follicles
· Ovulation is the ejection of the gametes from the ovary
· NOT directed connected to uterus; instead fimbriae create fluid currents that “wave” the egg down the fallopian tubes (uterine tubes) and into the uterus
Fallopian (Uterine) Tubes
[Section 27.2.5: The Uterine Tubes]
[Figure 27.14: Ovaries, Uterine Tubes, and Uterus]
· Not directly connected to the ovaries.
· This space between the gonads (ovaries) and the tubes is the reason that STDs like gonorrhea in females can spread outside of the reproductive system and cause inflammation of the pelvic region (pelvic inflammatory disease)
· Has 4 parts:
1. Fimbriae- fingerlike projections that move egg into tube
2. Infundibulum- expansion at beginning of tube, ciliated epithelium moves egg down tube, where most fertilization occurs
3. Ampulla- widened area of tube (majority of fertilizations occur here)
4. Isthmus- last point of tube, narrow, connects to uterus
· Most fertilization occurs in the upper 1/3 of the tube and then implants in the uterus. If the egg implants in the tubes, it is called an ectopic pregnancy. Because the tubes cannot support the growing fetus, this is very dangerous as rupturing can occur which endangers the mother’s life
Uterus
[Section 27.2.6: The Uterus and Cervix]
[Figure 27.14: Ovaries, Uterine Tubes, and Uterus]
· Between bladder and rectum
· Site of implanted fertilized ovum as well as fetal development
· 3 parts
1. Fundus- dome shaped
2. Cervix- inferior, narrow portion
3. Body – everything between the fundus and cervix
Uterine Wall
[Section 27.2.6: The Uterus and Cervix]
[Figure 27.14: Ovaries, Uterine Tubes, and Uterus]
Consists of 3 layers:
1. Perimetrium- outer layer, continuous with the visceral peritoneum, also called the serosa
2. Myometrium- muscular middle layer (3 layers of smooth muscle), responsible for labor contractions
3. Endometrium- two layers
· stratum basalis - covers myometrium and produces new functional zone each month
· stratum functionalis - very glandular and vascularized, supports embryo, sheds monthly during menstruation do to changes in ovarian hormone levels
Menstrual Cycle
[Section 27.2.7: The Menstrual Cycle]
[Figure 27.15: Hormone Levels in Ovarian and Menstrual Cycles]
hormonally regulated by FSH and LH from the anterior pituitary and by estrogen and progesterone from the ovaries
3 phases:
1. Menstrual phase (menses): approx. day 1-5, “sloughing off” of lining, accompanied with bleeding
2. Proliferative phase: approx. day 6-14, due to estrogen: endometrium is repaired, glands and vessels proliferate, and endometrium thickens. Ovulation occurs during this phase (ovulation is caused by LH from the pituitary)
3. Secretory phase: approx. day 15-28, due to progesterone: vascular supply further increases, size of glands increases and secrete nutrients for sustaining an embryo if present. If there is not an embryo present- the corpus luteum deteriorates, endometrium becomes spastic and menses will occur.
Lactation
[Figure 27.17: Anatomy of the Breast]
The mammary glands are modified sweat glands that produce milk in a process called Lactation
Each breast consists of:
· Lobes(15-20) Separated by fat and CT
· Lobules –contain alveoli
· Alveoli –milk secreting cells
· Lactiferous Duct-drain milk from lobules
· Lactiferous Sinus -empty milk into nipples
· Nipple –surrounded by pigmented areola