A membranous sac on the head of a sperm cell that contains enzymes that facilitate sperm penetration in to the egg during fertilization.
Synthetic hormones that mimic testosterone and stimulate the body to build muscle and increase strength. Abusing this can have many dangerous side effects.
Male accessory reproductive glands that release a clear slippery liquid immediately before ejaculation.
A gland that lacks ducts and releases its products (hormones) into the fluid just outside the cell.
Reproductive cells (sperm and egg) that contains only one copy of each chromosome. A sperm and egg fuse at fertilization, producing a zygote.
An ovary in a female or a testis in a male. The gonads produce gametes (sperm and egg) and sex hormones.
Chemical messengers released by cells of the endocrine system that travels through the circulatory system to affect receptive target cells.
A passage through the abdominal wall through which the testes pass in their descent to the scrotum.
Cells located between the seminiferous tubules in the testes that produce the steroid sex hormones, collectively called androgens.
A hormone secreted by the anterior pituitary gland that in females stimulates ovulation and the formation of the corpus luteum (which produces estrogen and progesterone)and prepares the mammary glands for milk.
LH (luteinizing hormone)
An accessory reproductive gland in males that surround the urethra as it passes from the bladder. Its secretions contribute to semen and serve to activate the sperm and to counteract the acidity of the female reproductive tract.
A loose fleshy sac containing the testes.
Secondary sex characteristics
The fluid expelled from the penis during a male orgasm. Consists of sperm and the secretions of the accessory glands.
A pair of male accessory reproductive glands located posterior to the urinary bladder. Their secretions contribute to semen and serve to nourish the sperm cells, reduce acidity in the vagina, and coagulate sperm.
The series of events within the seminiferous tubules that gives rise to physically mature sperm from germ cells. It involves meiosis and maturation.
The male gonads. The male reproductive organs that produce sperm and the hormone testosterone.
A sex hormone needed for sperm production and the maintenance of male reproductive structures. Produced primarily by the interstitial cells of the testes.
A hormone that influences another endocrine gland.
The muscular tube that transports urine from the floor of the urinary bladder to the outside of the body. In males, it also conducts sperm from the vas deferens out of the body through the penis.
A tubule that conducts sperm from the epididymis to the urethra.