Chapter 34, Problem 1O

Summary Introduction

To discuss:

The anatomy and physiology of female reproductive system.

Introduction:

The female reproductive system is composed of sex organs (internal and external), which function in the generation of progenies. At birth, the female reproductive system is undeveloped and it attains maturity at puberty (able to generate gametes and to carry a fetus).

Explanation of Solution

The female reproductive system is comprised of internal (vagina, ovaries, uterus, and fallopian tubes) and external structures (vulva). The hormones like progesterone and estrogen (female sex steroid hormone) and pituitary gonadotropin are involved in the generation of major sex structures, their maintenance, and reproductive functions.

Hormones:

The pituitary gonadotrophins, like luteinizing hormone and follicle-stimulating hormones, play a lead role in communication (hormonal) among ovaries and the pituitary gland for menstrual cycle regulation.

Estrogen:

The female sex characteristics (secondary) like distribution of hair and fat, development of skin, breast, and bone are stimulated by estrogen.

Progesterone:

It assists by forming optimum conditions for prenatal period in the endometrium (once ovulation is completed) and promotes menstrual cycle.

Ovaries:

Ovaries are (paired glands) situated on both the sides of the uterus. They act like reproductive glands and endocrine glands. They generate ova inside the ovarian follicles. Later, the ovum is released into the peritoneal cavity between fallopian tube and the ovary. Fimbriae (finger-like projections) lie next to each ovary. They catch the ova and direct it into the fallopian tube. Then, the ovum reaches the uterus by its lumen.

Ovaries generate two sex hormones, namely progesterone and estrogen (as endocrine glands). Chemically, these two hormones are comprised of numerous different substances. However, only two hormones such as estrogen estradiol and progesterone have the maximum physiological activity. Physiological activities of estradiol include gonadotropin regulation, sex characteristics (secondary) of women, vaginal mucosa thickening, endometrial growth, cervical mucus thinning, and breast ductal system growth. Progesterone is the chief secretory product of the corpus luteum. It has progestational properties like tissue growth promotion, secretory activity in the endometrium (menstrual cycle, estrogen-driven proliferative phase), uterine contraction inhibition, breast alveolar gland development, and increased cervical mucus viscosity (that give protection to the fetus from external source).

Fallopian tubes:

They are also referred to as uterine tubes, which are fine tubes creased with epithelium. They start from the ovaries and end at the uterus. Fallopian tube permits the egg cells from ovaries to uterus.

Uterus:

It comprises of three layers. They are as follows:

Perimetrium (protective): It acts as a protective layer (outer).

Myometrium (muscular): It offers even contractions (powerful) of the muscle.

Endometrium (inner muscular layer): It acts as the site of fertilized ovum implantation, fetus development, labor initiation, infant birthing, and menstruation.

Vagina:

It acts as a common passage for menstrual flow and for sperm after male ejaculation, receptacle for the penis (sexual intercourse), and for birthing.

Vulva:

It is the external part of the female genitals. It defends urinary opening, vagina, vestibule, and sexual organs.

Conclusion

The female reproductive system is involved in the generation of progenies.