Testicles
Produce sperm cells that fertilize the female’s egg
Lie externally to the abdomen
Testosterone
Hormone that makes the appearance and behavior of a male masculine and testosterone
Epididymis
Where sperm are stored from the testicle to mature
Scrotum
A sac that contains and protects the testicles, regulated the temperature
Can retreat towards the body when warmth is needed and can descend when cooling is needed
Vas Deferens
Transports sperm from the epididymis to the urethra
Urethra
Large muscular canal extending from the urinary bladder. Through this urine and semen are excreted
Accessory Sex Glands
Seminal vesicles, prostrate, and bulbouerthral gland
Primarily add to the sperm fluid to provide health and nutrition to sperm
Penis
Organ of copulation. Characterized by spongy, erectile tissue. Provides passageway for semen and urine
Seminiferous tubes
Found inside the testes and the site of sperm production
The vas deferens takes the sperm where?
To the prostate gland where accessory secretions are added to the sperm
Sperm cells contain
Flagella for movement
Mitochondria for energy
DNA for fertilization
Pituitary gland helps to control function of
Testes
Luteinizing Hormone (in males)
Stimulates the production of testosterone
Follicle Stimulating Hormone (in males)
Facilitates sperm production
Fibroelastic Penis
Uses sigmoid flexure and retractor muscle to become erect
Vascular Penis
Will fill up with blood to become erect (humans and horses)
Thermoregulation
Regulation of temperature of testes to support fertile sperm production
Cryptochidism
When one or neither testes descend into the scrotum during fetal stages
Convoluted
Contains many veins
Vasectomy
Procedure to sterilize a male
Spermatogenesis
Formation and growth of sperm
Testosterone
Origin and function
Origin: Leydig cells found in the testes
Promotes: spermatogenesis and secondary sex characteristics
Tunica Dartos Muscle
Origin and function
Origin: Scrotum
Functions: Suspend testes in scrotum and provide heat/cooling system
The 3 Parts of the Spermatic Cord
- Ductus Deferens
- Pampiniform Plexus
- Cremaster Muscle
Ductus(/Vas) Deferens Function
Move fertile sperm from the tail of the epididymis to penis
Pampiniform Plexus Function
Composed of testicular artery and veins to cool blood before scrotum
Cremaster Muscle
Supports testes, pull up testes during fight/flight (short period of time)
Gubernaculum Function
Pulls testes through inguinal ring into the scrotum
Inguinal ring
Opening between the body and scrotum
Unlilateral Cryptorchidism
Only 1 testis descends into the scrotum
Bilateral Cryptorchidism
Both testes don’t descend into the scrotum
3 functions of the Epididymis
Sperm transport
Sperm maturation
Sperm storage
Head of Epididymis (caput)
State of sperm
Entry point of Epididymis for sperm
sperm are not motile or fertile
Body of the epididymis (corpus)
State of sperm
Maturation occurs here
Sperm some what motile and fertile
Tail of the Epididymis (cavada)
State of sperm
Sperm is stored here (5-10 ejaculations)
sperm are motile and fertile
sperm can bind to an egg
The 2 parts of the fibroelastic penis
Sigmoid flexure
retractor penis muscle
Sigmoid flexure
‘S’ shaped curve that holds the penis within the body when not erected or helps with erection
3 Sterilization Techniques
Castration
Vasectomy
Shortening of the spermatic cord
Castration
Removal of the testicles, no sexual acts
Vasectomy
Cutting to sever the Ductus Deferens
Shortening of the spermatic cord effect
Raises the testicles closer to the body - makes the sperm too close to the body and too hot - making them infertile
Thermoregulation is important because
Sperm will die if too hot, too cold, or comes into contact with blood
Thermoreceptor function
Sends messages to the brain if too hot/cold
Sweat gland function in male reproduction
located on the scrotum and will allow for cooling
Tunica Dartos Muscle function
Expand when too hot (testes away from body)
Pull up when too cold (testes to the body)
Leydig cell
Function and location
Function : produce testosterone
Location : outside the seminiferous tubules
Sertoil cell
Function and location
Function : Protect and aid in growing sperm
Location : Inside seminiferous tubules
Steps of sperm transport
1 - Seminiferous tubules 2 - Epididymis 3 - Vas deferens 4 - Penis 5 - Into female tract