I. Read and translate one of the following texts: Text a female reproductive system

As in the male, female reproduction is under the control of hormonal and nervous regulation. Development of the female reproductive organs and normal function depend on the relative levels of a number of hormones in the body.

The female reproductive system consists of ovaries, uterine tubes, uterus, vagina, external genital organs, and mammary glands. The female reproductive system produces ova and provides a place for the embryo growth.

There are two fallopian tubes (also called uterine tubes) one on each side of the uterus. Each of these tubes contains a passageway no wider than a needle. The fallopian tubes transport the oocyte or zygote (the fertilized oocyte) from the ovary to the uterus.

Two ovaries are small organs approximately 2 to 3.5 cm long and 1 to 1.5 cm wide. They are located in pelvic cavity. Between puberty and menopause, the ovaries generally release one egg each month. They also produce the female sex hormones (estrogen and progesterone). The union of the male and female sex cells in humans takes place within the female body. Fertilization is the process of penetrating the secondary oocyte by the spermatozoon. It is completed with the fusion of the male and female pronuclei. If fertilization takes place, the new cell formed begins a nine-month period of development within the uterus.

The size and shape of the uterus is as a medium-sized pear and is approximately 7.5 cm long and 5 cm wide. The walls of uterus are thick and consist of three layers: serous, muscular, and mucous. The powerful muscles contract during childbirth to push the baby out.

The narrow neck of the uterus is called the cervix, and it also has thick walls. The mucus fills the cervical canal and acts as a barrier to substances that could pass from the vagina into the uterus. Ordinarily, the opening of the cervix is exceedingly small. During childbirth, the cervical opening expands to allow passage of the baby.

The cervix extends into vagina, which is a muscular tube about 10 cm long. The wall of the vagina consists of an outer muscular layer and an inner mucous membrane. Most of the time the walls of vagina touch, but they can expand to accommodate a baby. The internal reproductive organs are held in place within the pelvis by a group of ligaments.

The opening to vagina is protected by external genitals.

Mammary glands are the organs of milk production and are located within breasts. The mammary glands are modified sweat glands. Externally, the breasts of both males and females have a raised nipple surrounded by a circular, pigmented areola (pl. areolae). The female breasts begin enlarging during puberty under the influence of estrogen and progesterone.

Text B

Male reproductive system

The main function of the male reproductive system is producing sperm cells and transporting them to the female reproductive system.

The male reproductive system consists of the testes (or testicles), epididymides, ductus deferentia, urethra, seminal vesicles, prostate gland, bulbourethral glands, scrotum, and penis. Sperm cells are very temperature sensitive and do not develop normally at usual body temperatures. The testes and epididymides are located outside the body cavity where the temperature is low.

The testes are contained in a pouch of skin, called the scrotum. In each testis there is a tightly packed mass of coiled tubes surrounded by a protective capsule. At puberty the testes begin to produce the sperm cells (spermatozoa) that are used in reproduction. This process continues throughout life. In addition to producing sperm cells the testes secrete the male hormone testerone, which plays an important role in the development and maintenance of the typical masculine physical characteristics, such as facial hair, greater muscle mass and strength, and a deeper voice. The sperm cells are constantly being produced within each testis. They are transported through the epididymides and the ductus deferentia and then stored in the seminal vesicles. The mixture of the sperm cells with the fluids formed by the seminal vesicles and the prostate gland forms the semen that is ejaculated during sexual activity. Although sperm cells make up only a small portion of the semen, a single ejaculation contains as many as 500 million sperm. After sexual intercourse, one of these cells may reach and fertilize an egg in the female. The prostate gland contributes fluids to the semen. As a man ages, the prostate gland frequently enlarges. The urethra, which runs the length of the penis through its center, carries urine during voiding and semen during ejaculation. The urethra exits from the pelvis and passes through the penis to the outside of the body.

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