A&P 2 - Module 11 (Male Reproductive System)

Gamete

A haploid reproductive cell that participates in the formation of a zygote; sex cell or germ cell.

Primary Sex Characteristic

A reproductive organ present at birth that is directly involved in the production of gametes and reproduction.

Secondary Sex Characteristic

A physical trait that develops at puberty under the influence of sex hormones and is not directly involved in reproduction.

Genitalia

The internal and external reproductive organs of an individual.

External Genitalia

The reproductive organs located outside the body that are involved in sexual function and reproduction.

Internal Genitalia

The reproductive organs located inside the body that are involved in gamete production and reproductive processes.

Accessory Organ

A structure of the reproductive system that assists in reproduction but does not produce gametes.

Penis

The male external reproductive organ that delivers sperm to the female reproductive tract and also serves as a conduit for urine.

Urethra

A tube that carries urine from the bladder and, in males, also carries semen during ejaculation.

Scrotum

A sac of skin that holds the testes outside the body to maintain a temperature suitable for sperm production.

Testis

The paired male gonad located within the scrotum responsible for producing sperm and testosterone.

Epididymis

A coiled duct on the posterior surface of each testis where sperm mature and are transported from the testis to the ductus (Vas) deferens.

Ductus (Vas) Deferens

A muscular tube that transports sperm from the epididymis to the urethra.

Seminal Gland

A paired male reproductive accessory gland on the posterior side of the urinary bladder that secretes seminal fluid.

Prostate

A male reproductive accessory gland on the inferior side of the urinary bladder that secretes seminal fluid.

Bulbourethral Gland

A small male reproductive accessory gland that secretes seminal fluid that lubricates the urethra and neutralizes acidic urine residues.

Dartos Muscle

A layer of smooth muscle in the scrotum that wrinkles the skin to help regulate testicular temperature.

Cremaster Muscle

A skeletal muscle in the scrotum that raises and lowers the testes to regulate temperature.

Spermatic Cord

A bundle of vessels, nerves, and ducts that run through the inguinal canal and support the testes.

Inguinal Canal

A passage through the male abdominal wall that allows the testes to descend and exit the body cavity during development and then the spermatic cord to pass into the scrotum.

Hernia

A condition in which an organ or tissue protrudes through a weakened area of the abdominal wall.

Spermatogenesis

The process by which male gametes (sperm) are produced through mitosis and meiosis.

Mitosis

A type of cell division that produces two genetically identical daughter cells with the same chromosome number as the parent cell.

Meiosis I

The first division of meiosis in which homologous chromosomes separate, reducing the chromosome number by half.

Meiosis II

The second division of meiosis in which sister chromatids separate.

Spermiogenesis

The final stage of spermatogenesis in which spermatids physically mature into sperm.

Chromosome

A condensed form of DNA that carries genetic information.

Diploid

A cell containing two complete sets of chromosomes, one from each parent.

Haploid

A cell containing a single set of chromosomes.

Daughter Cell

A cell produced as a result of cell division.

Spermatogonium

A diploid germ cell in the seminiferous tubules that divides by mitosis to begin sperm production.

Primary Spermatocyte

A diploid cell that forms from the mitotic division of a spermatogonium; enters meiosis I to form two secondary spermatocytes.

Secondary Spermatocyte

A haploid cell produced by meiosis I that quickly enters meiosis II to form two spermatids.

Spermatid

A haploid cell produced by meiosis II that will differentiate into a sperm.

Sperm

The male gamete.

Seminiferous Tubule

A coiled tubule within the testes where spermatogenesis occurs.

Interstitial Cell

A cell located between seminiferous tubules in the testes that produces testosterone.

Androgen

A class of steroid hormones, including testosterone, that promote male reproductive development and secondary sex characteristics.

Nurse Cell

A cell located in the wall of the seminiferous tubule that supports and nourishes developing sperm; sustentacular cell or Sertoli cell.

Spermiation

The release of mature sperm from nurse cells into the lumen of the seminiferous tubules.

Capacitation

The process of functional maturation that sperm undergo to become capable of fertilization; the addition of seminal fluid to sperm and deposition of semen in the female reproductive tract.

Semen

The mixture of sperm and seminal fluid.

Ejaculation

The forceful expulsion of semen from the urethra.

Root (of the penis)

The fixed, internal portion of the penis that anchors it to the pelvic structures.

Body (of the penis)

The elongated, external portion of the penis that contains erectile tissues.

Glans (of the penis)

The enlarged, sensitive tip of the penis.

Corpora Cavernosa (male)

Paired columns of erectile tissue in the root and body of the penis that fill with blood to produce an erection.

Corpora Spongiosum (male)

A column of erectile tissue that surrounds the urethra through the body of the penis and forms the glans of the penis.

Prepuce (male)

The fold of skin that covers the glans of the penis; foreskin.

Gonadotropin Releasing Hormone (GnRH)

A hypothalamic hormone that stimulates the anterior pituitary to secrete LH and FSH.

Luteinizing Hormone (LH) (male)

An anterior pituitary hormone that stimulates interstitial cells to secrete testosterone.

Follicle-Stimulating Hormone (FSH) (male)

An anterior pituitary hormone that stimulates nurse cells to promote spermatogenesis.

Inhibin (male)

A gonadal hormone produced by nurse cells that inhibits FSH secretion to regulate sperm production.

Birth Control

Methods or devices used to prevent pregnancy.

Male Condom

A barrier device worn over the penis that prevents sperm from entering the female reproductive tract.

Sexually Transmitted Infection / Disease (STI/STD)

An infection transmitted primarily through sexual contact.

Vasectomy

A surgical procedure in which the ductus (Vas) deferens is cut or sealed to prevent sperm transport through the male reproductive tract.