The sperm head is covered by a structure called:

Reproduction in humans

Read the following passage carefully and answer the given questions.

The female reproductive system consists of a pair of ovaries, a pair of oviducts, a uterus, a vagina, external genitalia, and a pair of mammary glands. The ovaries produce the female gamete and some steroidal hormones. Ovarian follicles in different stages of development are embedded in the stroma. The oviducts, uterus and vagina are female accessory ducts. The uterus has three layers, namely perimetrium, myometrium and endometrium. The female external genitalia includes mons pubis, labia majora, labia minora, hymen and clitoris. The mammary glands are one of the female secondary sexual characteristics. Spermatogenesis results in the formation of sperm that is transported by the male sex accessory ducts. A normal human sperm is composed of a head, neck, a middle piece and tail. The process of formation of mature female gametes is called oogenesis. The reproductive cycle of female primates is called the menstrual cycle. The menstrual cycle starts only after attaining sexual maturation. During ovulation, only one ovum is released per menstrual cycle. The cyclical changes in the ovary and the uterus during the menstrual cycle are induced by changes in the levels of pituitary and ovarian hormones.