Identify the location where the sex cells of each reproductive system mature.

The correct answer is D -ovary for the left (female reproductive system) and Q-epididymis for right (male reproductive system).

Ovaries are the primary female sex organs that produce the female gamete (ovum) and several steroid hormones (ovarian hormones). The ovaries are located one on each side of the lower abdomen. Each ovary is about 2 to 4 cm in length and is connected to the pelvic wall and uterus by ligaments. The formation of a mature female gamete is called oogenesis. Oogenesis takes place in ovary and is initiated during the embryonic development stage when a couple of million gamete mother cells (oogonia) are formed within each fetal ovary.

Testis are the primary sex organ in males.  Spermatogenesis is process by which sperm is produced in testis. Spermatogenesis starts at the age of puberty due significant increase in the secretion of gonadotropin releasing hormone (GnRH). This, if you recall, is a hypothalamic hormone. Sperms released from the seminiferous tubules, are transported by the accessory ducts. Secretions of epididymis, vas deferens, seminal vesicle and prostate are essential for  maturation and motility of sperms. The seminal plasma along with the sperm constitutes the semen.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.