Module 3, Lecture 2: Male reproduction

A comprehensive set of vocabulary flashcards covering the major terms and concepts in the lecture on male reproduction.

Testis

Primary male reproductive organ that produces sperm and testosterone.

Sertoli cells

Nurse cells in the seminiferous tubules that support developing germ cells, form the blood-testis barrier, secrete ABP, and produce inhibin.

Leydig cells

Interstitial cells that synthesize testosterone under LH stimulation.

Spermatogonia

Germline stem cells located at the basal lamina of seminiferous tubules that divide to produce primary spermatocytes.

Spermatogonia Type A

Spermatogonia that remain at the basal lamina to maintain the germ cell pool.

Spermatogonia Type B

Spermatogonia that move toward the lumen and differentiate into primary spermatocytes.

Primary spermatocyte

Diploid cell derived from spermatogonia that enters meiosis I.

Secondary spermatocytes

Haploid cells produced after meiosis I.

Spermatids

Haploid cells produced after meiosis II; undergo spermiogenesis to become spermatozoa.

Spermatozoa

Mature male gametes capable of fertilization.

Spermatogenesis

Process of sperm production in the seminiferous tubules, including mitosis, meiosis, and spermiogenesis.

Spermiogenesis

Cytodifferentiation of spermatids into elongated, motile spermatozoa.

Blood-testis barrier

Immune-privileged barrier formed by tight junctions between Sertoli cells to protect developing germ cells.

Tight junctions

Connections between Sertoli cells that form the blood-testis barrier.

ABP (androgen-binding protein)

Sertoli-cell protein that binds testosterone and concentrates it near germ cells.

Inhibin

Hormone from Sertoli cells providing negative feedback to FSH.

Testosterone

Primary male sex hormone produced by Leydig cells; supports spermatogenesis and secondary sexual characteristics; subject to negative feedback.

LH (Luteinizing Hormone)

Gonadotropin that stimulates Leydig cells to produce testosterone.

FSH (Follicle-Stimulating Hormone)

Gonadotropin that stimulates Sertoli cells to support spermatogenesis and ABP production.

GnRH (Gonadotropin-Releasing Hormone)

Hypothalamic hormone that stimulates the anterior pituitary to release LH and FSH.

HPG axis

Hypothalamic-Pituitary-Gonadal axis; regulatory loop controlling gonadotropin and sex hormone production.

Epididymis

Duct where sperm mature and are stored after leaving the testis.

Ductus deferens (vas deferens)

Tube that transports sperm from the epididymis to the urethra during ejaculation.

Seminal vesicles

Accessory glands that secrete components of semen to nourish and support sperm.

Prostate

Accessory gland that contributes prostatic fluid to semen.

Bulbourethral gland

Accessory gland that secretes lubricating mucus into the urethra.

Scrotum

External pouch that houses the testes and helps regulate temperature.

Tunica albuginea

Dense fibrous capsule surrounding each testis.

Tunica vaginalis

Serous covering of the testis derived from peritoneum.

Spermatic cord

Bundle containing the vas deferens, testicular vessels, nerves, and connective tissue.

Cremaster muscle

Muscle that raises and lowers the testes to regulate temperature.

Dartos muscle

Smooth muscle layer in the scrotal wall that wrinkles the scrotal skin.

Pampiniform venous plexus

Venous network around the testicular artery that cools arterial blood.

Acrosome

Cap-like structure over the head of the sperm containing enzymes for fertilization.

Midpiece

Part of the sperm containing mitochondria to supply energy for movement.

Tail (flagellum)

Motile tail of the sperm; contains the axoneme for propulsion.

Meiosis I

First meiotic division; homologous chromosomes separate to form secondary spermatocytes.

Meiosis II

Second meiotic division; sister chromatids separate to form spermatids.

Mitosis

Cell division producing two genetically identical diploid daughter cells; initial proliferation of spermatogonia.

Prenatal testosterone surge

Fetal testosterone production by Leydig cells critical for male differentiation.

Postnatal testosterone peak

Rise in testosterone after birth before puberty.