Chapter 26
The Reproductive System
By Boundless
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The male reproductive system includes external (penis, scrotum, epididymus, and testes) and internal (accessory) organs.
The purpose of the scrotum is to provide the testes with a chamber of appropriate temperature for optimal sperm production.
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The testis is homologous to the ovary in that it produces the male gamete (sperm) while the ovary produces the female gamete (egg).
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In human males, the penis serves as both a reproductive organ and as a urinal duct.
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Testes ducts, which include the seminiferous tubules and vas deferens, are involved in the creation or transportation of sperm.
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The accessory sex glands produce seminal fluid and clean and lubricate the urethra.
Physiological changes occur to male genitalia during sexual arousal.
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Sperm are the male "seeds," germ cells, or gametes.
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Male gametes (sperm cells) are haploid cells produced via spermatogenesis.
Semen is a fluid produced by the seminal vesicles.
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The male reproductive system is regulated by the production, stimulation, and feedback of specific hormones.
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The human female reproductive system contains two main parts: the uterus and the ovaries, which produce a woman's egg cells.
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The ovaries are the ovum-producing organs of the internal female reproductive system.
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The uterus is the largest and major organ of the female reproductive tract that is the site of fetal growth and is hormonally responsive.
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The Fallopian tubes, or oviducts, connect the ovaries to the uterus.
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The vagina is the female reproductive tract and has two primary functions: sexual intercourse and childbirth.
The vulva is the external genitalia of the female reproductive tract, situated immediately external to the genital orifice.
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The perineum is the region between the genitals and the anus, including the perineal body and surrounding structures.
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A mammary gland is an organ in female mammals that produces milk to feed young offspring.
Oogenesis is the maturation of the female gametes through meiotic division.
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The menstrual cycle is the physiological process that fertile women undergo for the purposes of reproduction and fertilization.
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The uterine cycle describes a series of changes that occur to the lining of the uterus, or endometrium, during a typical menstrual cycle.
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The menstrual cycle is controlled by a series of changes in hormone levels, primarily estrogen and progesterone.
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Estrogen and progesterone have several effects beyond their immediate roles in the menstrual cycle, pregnancy, and labor.
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Female sexual arousal causes physiological changes including increased blood flow to the genitals and enlargement and lubrication of the vagina.