lab 10 - male reproductive system

Scrotum

Testes (singular = testis)

Interstitial (Leydig) cells

• Produce testosterone

• Located in the connective tissue between seminiferous tubules

Seminiferous tubules

• Where sperm is produced

• Cross section

Tunica albuginea

Dartos muscle

Epididymis

• Allows sperm to mature and stores them before ejaculation

Spermatic cords

• Contains vas deferens, blood and lymph vessels and nerves

Vas (ductus) deferens

• Muscular tube where sperm travels from the epididymis to the ejaculatory duct

Seminal vesicle

• Contributes about 60% of the fluid in semen

Ejaculatory duct

• Where the vas deferens and the duct of the seminal vesicle meet and empty into the urethra

Prostate gland

• Secretes a thin, milky fluid that makes up about 30% of the semen

Prostatic urethra

Membranous urethra

• Passes through the prostate gland

Bulbourethral (Cowpers) gland

• Produces a clear slippery fluid that lubricates the head of the penis

• The fluid also neutralizes the acidity of residual urine in the urethra that can be harmful to sperm

Penis

Penile urethra

Corpus cavernosum

• 2 cylindrical erectile tissues located on the dorsal side of the penis

Crus

• Each corpus cavernosum diverges toward the inside of the body like the arms of a Y

• Each arm is called a crus

Corpus spongiosum

• A single erectile body that passes along the ventral side of the penis and encloses the penile urethra

Bulb

• The corpus spongiosum terminates internally as a dilated bulb

Glans penis

• The enlarged, sensitive tip of the penis that contains a high concentration of nerve endings and is covered by the prepuce in uncircumcised males.

Prepuce

• Also called foreskin

Sperm head

• The front part of a sperm cell that contains the nucleus and genetic material.

Acrosome

• A lysosome in the form of a cap that contains enzymes used to penetrate the egg

DNA

• 23 chromosomes

• Located within the nucleus in the head of the sperm

Midpiece

• The section of a sperm cell between the head and the tail, containing mitochondria that provide energy for motility

Sperm tail

• The elongated structure that propels the sperm forward, enabling it to swim toward the egg

Spermatogenesis

• The process of sperm cell development from spermatogonia to mature spermatozoa, occurring in the testes.

Diploid vs Haploid

Diploid: contain 2 sets of chromosomes (46)

Haploid: contain 1 set (half of normal) 23

What is this?

Testes