MALE REPRODUCTIVE SYSTEM

Mrs. Alexandra Martínez

GCI Science Teacher

What´s the role of males in sexual reproduction?

• The main goal of the MRS is to

produce sperm cells and deliver

them to the FRS to achive his main

objective of FERTILIZATION!!

MALE´S STRUCTURES & FUNCTIONS

• TestesEgg shaped structures located outside the abdominal cavity, outside of the body insde a sack called SCROTUM. They are located outside to ensure the optimal temperature of 34ºC for sperm development.Testes is where sperm and testosterone (important male hormone is produced).They contain small tubules called SEMINIFEROUS TUBULES, where meiosis (spermatogenesis) occurs and sperm cells are produced.

• Epididymis Located just above each testicle, consists of more tubules, where sperm go to mature and develop a tail to capable of moving.

MALE´S STRUCTURES & FUNCTIONS

• Vas DeferensTubes that connect the testes to the urethra, carrying sperm cell and other semen content. Urethra is the same duct through which urine leaves the male body.

• Glands and VesiclesAs the sperm advances to be ejected from the penis, it passes along other structures collecting fluids that will together form the SEMEN.SEMINAL VESICLE: secrets fructose to enrich the content of semen.PROSTATE GLAND: secrets an alkaline substance to neutralize vagina´s acidity.BULBOURETHRAL GLAND: secrets an alkaline substance to neutralize any acid left over in the urethra due to urine.

MALE´S STRUCTURES & FUNCTIONS

• Sperm´s Pathway: seminiferous tubules – epididymis – vas deferens – seminal vesicle – prostate gland – bulbourethral gland – urethra – penis.

MALE´S STRUCTURES & FUNCTIONS

• Semen ContentSemen is the fluid that is ejected from the penis, carrying sperm to accomplish fertilization.– Sperm: male gamete carrying genetic info.– Protein: to provide a clogging substance avoiding

the semen being too liquidly and fall out of the vagina.

– Fructose: which is a carbohydrate to provide energy for the sperm to survive the long journey.

– Alkaline solution: to neutralize vagina´s acidity and give sperm a less hostile environment so that it can survive.

MALE´S STRUCTURES & FUNCTIONS

• Sperm:– Head: Carries the nucleus

with chromosomes. At the tip is the acrosome, which carry enzymes to soften the egg´s layer.

– Midpiece: Mitochondria which is the motor responsible for maintaining high energy levels.

– Tail: acts like a propeller, designed for speed and strength

MALE´S STRUCTURES & FUNCTIONS

• HormonesSeveral hormones important for the well functioning of the MRS

– LH: stimulates the secretion of testosterone.– FSH: stimulates sperm production– Testosterone: stimulates sperm production. Begins to be

produced during puberty.

• Male infertilitySome causes of male infertility

– Showers in hot tubs, too hot showers, sauna.– No sperm movement– Not enough sperm in semen. Normal count is 300-400

million in 3.5ml.