Male / AMAB Reproductive System

What are the functions of the male reproductive system

Produces and transports sperm and produces hormones

What are gonads

Sex organs (testes) that secrete hormones and produce sperm or ova

What is the function of the scrotum

Holds the testes outside the abdominopelvic cavity and regulate temperature

Why must the testes remain cooler than body temperature

The scrotum keeps them approximately 3C cooler for proper sperm development

What does the dartos muscle do

Wrinkles the scrotal skin

What does the cremaster muscle do

Elevates the testes closer to the body

What happens when the testes move closer to the body

Scrotal skin wrinkles, decreasing surface area

What happens when the testes move farther from the body

Scrotal skin loosens, increasing surface area

What are the two main function of the testes

Sperm production and hormone production

What are seminiferous tubules

The location of sperm production within the testes

What are myoid cells responsible for

Contracting to push sperm and testicular fluids through seminiferous tubules and out of the testes

What do interstitial cells produce

Androgens, including testosterone

What are sustentacular cells

Cells that surround seminiferous tubules and support developing sperm

What is the blood-testis barrier

Tight junctions formed by sustentacular cells that separate developing sperm from the immune system

Why is the blood-testis barrier important

Protects developing sperm from the immune system because sperm have new antigens

What do sustentacular cells secrete

Testicular fluid

Substances that stimulate mitosis

Androgen-binding protein

Inhibin

What is the function of testicular fluid

Provides nutrients for developing sperm cells

What is the function of phagocytosis by sustentacular cells

Removes degenerating spermatogonia cells and excess cytoplasm from developing sperm

What is spermatogenesis

The process of sperm production

What is spermiogenesis

The process of sperm maturation

When does sperm production being

At puberty and continues throughout life

What are spermatogonia

Undifferentiated germ cells that divide by mitosis before differentiating into primary spermatocytes

What happens to primary spermatocytes

They undergo meiosis

What is produced at the end of meiosis

Haploid spermatids

What happens during spermiogenesis

Spermatids mature through cell elongation

Shedding excess cytoplasm

Acrosome development

Additional mitochondria

Flagellum formation

What develops during sperm maturation

Sperm mobiity

What is the function of the acrosome

Covers the head of the sperm and contains enzymes that aid in fertilization

What is the function of sperm mitochondria

Perform cellular respiration

What is the function of the flagellum

Provides mobility

What does the sperm nucleus contain

Genetic information

What percentage of semen volume is sperm

~ 2-5%

What is the function of the epididymis

Sperm maturation and storage, absorbs excess testicular fluid and provides nutrients

Approximately how long does sperm take to reach the end of the epididymis

~ 12 days

What happens to sperm if ejaculation does not occur

Sperm are reabsorbed

What is the function of the ductus deferens

Carries sperm and testicular fluid from the epididymis to the ejaculatory duct

Where is the ejaculatory duct formed

At the junction of the seminal vesicle duct and ductus deferens

Where does the ejaculatory duct travel

Through the prostate

What is the function of the urethra

Transports semen and connects to the outside of the body

What are the three sections of the male urethra

Prostatic

Membranous

Spongy

What do the seminal vesicles secrete

Seminal fluid- contributing ~ 60-70% of semen volume

What is the function of fructose in seminal fluid

Provides sugar as an energy source

What do prostaglandins from seminal vesicles do

Stimulate smooth