testis: Quick Facts

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Also Known As	testicle • testes

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Medical illustration of a human male testis with labeled structures including the epididymis, ductus (vas) deferens, testicular artery, pampiniform plexus, efferent ductules, septa, lobules, and tunica albuginea, showing the anatomy and connections of the male reproductive system.

human sperm cells

Medical illustration of the male reproductive system in cross-section, showing labeled anatomical structures such as the penis, testis, scrotum, prostate, urethra, seminal vesicle, and associated ducts and glands.

Major glands of the human endocrine system. The hypothalamus stimulates the pituitary gland and influences food intake, weight regulation, fluid intake and balance, thirst, body heat, and the sleep cycle. Pituitary hormones stimulate growth, egg and sperm development, milk secretion, and release of hormones by other glands. The pineal gland may play a significant role in sexual maturation and the circadian rhythm. Thyroid hormones regulate the metabolic rate of tissues, stimulate the contraction of heart muscle, and are necessary for normal growth and brain development before birth and during infancy. Parathyroid hormone regulates calcium, phosphorus, and magnesium levels. The adrenal glands regulate salt and water retention, some reactions of the immune system, and blood pressure. The islets of Langerhans regulate blood sugar levels. The ovaries and testes produce hormones that regulate the reproductive system and that produce male and female secondary sex characteristics.

The principal glands of the female and male human endocrine systems.

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Topics

Leydig cell spermatogenic cell Sertoli cell recrudescence seminiferous tubule rete testis tunica albuginea spermatogenesis epididyme ductus epididymidis ovary thyroid gland adrenal gland pancreas pituitary gland hypothalamus pineal gland thymus parathyroid gland kidney

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