The Reproductive SystemPart 1

Chapter 39Section 3

• In humans, as in other vertebrates, the reproductive system produces, stores, and releases specialized sex cells known as gametes.

• These cells are released in ways that make possible the fusion of sperm and egg to form a zygote,

• the single cell from which all cells of the human body develop.

Sexual Development

• For the first six weeks of development, human male and female embryos are identical in appearance.

• During the seventh week, the primary reproductive organs—the testes in males and the ovaries in females —begin to develop

• The testes begin to produce testosterone.

• Or, the ovaries produce estrogen

• These hormones determine whether the embryo will develop physically into a male or female.

• After birth, the gonads produce small amounts of sex hormones that continue to influence the development of the reproductive organs.

Puberty • Neither the testes nor the ovaries are capable of

producing active reproductive cells until puberty.(test question)

• Puberty is a period of rapid growth and sexual maturation during which the reproductive system becomes fully functional .

• It usually occurs any time between the ages of 9 and 15, and, on average, begins about one year earlier in females than in males. (test question)

The Male Reproductive System

• The main function of the male reproductive system is to produce and deliver sperm. (test question)

• The primary male reproductive organs, the testes, develop within the abdominal cavity. Just before birth (and sometimes just after) the testes descend through a canal into an external sac called the scrotum.

• Sperm are formed in the testes. (test question)

Sperm exits the body through theUrethra(test question)

Sperm is the male gamete

Define the Following Words

puberty scrotum follicleepididymis vas deferens

urethra penis ovulation Fallopian tube

seminiferous tubule