ABSTRACT
Study objectives Explain the process and the purpose of gametogenesis Describe the location and the function of each of the organs and structures in the male reproductive system including the testes, seminiferous tubules, testicular interstitial tissue, scrotum, epididymides, vas deferens, ejaculatory ducts, penis, prostate gland, seminal vesicles, and bulbourethral glands Distinguish between Sertoli cells and Leydig cells List the functions of testosterone in the male Describe the location and the function of each of the organs and structures in the female reproductive system including the ovaries, fallopian tubes, uterus, endometrium, myometrium, and the vagina Distinguish between granulosa cells and thecal cells Explain the events of the follicular phase of the ovarian cycle including changes in hormone (follicle-stimulating hormone [FSH], luteinizing hormone [LH], estrogen, and progesterone) secretion, follicular development, and the endometrium Explain the events of the luteal phase of the ovarian cycle including changes in hormone (FSH, LH, estrogen, and progesterone) secretion, corpus luteum development, and the endometrium Describe how FSH, LH, estrogen, and progesterone regulate the ovarian cycle List the other functions of the female sex hormones
. Introduction Unlike each of the other organ systems discussed in this textbook, the reproductive system does not contribute to the maintenance of homeostasis. However, it is essential for producing offspring. Reproduction is the process of passing genetic material from one generation to the next. As such, it involves gametogenesis, or the production of sex cells (gametes). The male gamete, or sperm, contains 23 chromosomes, and the female gamete, or ovum, also contains 23 chromosomes. The fertilization of the ovum by the sperm results in the formation of a zygote with the full human complement of 46 chromosomes. This chapter will discuss the following:
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Gametogenesis (spermatogenesis and oogenesis) Male reproductive system Testosterone Female reproductive system Ovarian cycle
Germ cells in the male are referred to as spermatogonia. At puberty, these germ cells, which are found in the Sertoli cells of the testes, divide. Some of the cells reproduce themselves by way of mitosis. The spermatogonia may also undergo meiosis and become primary spermatocytes. Meiotic division by each primary spermatocyte eventually leads to the formation of four spermatozoa, or sperm. The entire development process takes about 64 days.
