Human Development

Overview of the Reproductive System

The male and female reproductive systems have similar features and functions.

Both the male and female reproductive systems are essential to ensure the cycle of life continues through the production of offspring. Sexual reproductive processes are used to combine genetic information from both parents to create unique offspring. Both the male and female reproductive systems share similar gonads, ducts, and accessory glands. A gonad is a reproductive organ that produces gametes and sex hormones. A gamete is a mature haploid cell (having one set of chromosomes) that carries the genetic material for potential offspring. In females, the gametes are eggs (ova) produced in gonads called ovaries, whereas in males, the gametes are sperm produced in gonads called testes. During reproduction, the respective systems must transport the gametes to the site of fertilization, which is where a male and female gamete unite. Both systems use ducts to transport the gametes. In females, gametes move through the uterine tubes (fallopian tubes), while in males the sperm first travel through the seminiferous tubules followed by a series of other ducts before exiting the male reproductive system through a tube called the ureter that traverses the penis. During sexual intercourse, the sperm then travel through the vagina and uterus of the female reproductive system to reach the egg in the uterine tube. When an egg and sperm unite and combine, they form a fertilized egg called a zygote, which is a diploid cell (having two sets of chromosomes). The zygote undergoes cellular divisions to create an embryo.

For fertilization to be possible, the reproductive organs from both males and females must mature. This happens at the start of puberty when sex hormones secreted by gonads trigger functional maturation to begin. In females these hormones are primarily estrogen and progesterone, while the main sex hormones that affect males are androgens. Sex hormones also affect sexual behavior and sexual drive and are responsible for characteristic male and female secondary features. Erectile tissues are found in the penis of males and in the clitoris of females. In males this tissue is important for sperm delivery, and in both males and females it contains sensory receptors responsible for a pleasurable sensation.