Reproductive System - Unit 4 Flashcards
What are the Functions of the Reproductive System?
- Production of gametes (sperm/egg cells)
- Fertilization of gametes (reproduction)
- Development and nourishment of the new individual
- Producing reproductive hormones
Organs of the male reproductive system are specialized to…
– Produce and maintain sperm cells
– Transport the sperm cells and supporting fluid to the outside
– Secrete male sex hormones
Where are the Testes located? How do they Develop?
They are located outside the body cavity in a sac-like structure called the scrotum
– Sperm require lower-than-body
temperature for development
The testes develop in the abdominopelvic cavity and over time after birth they descend to the lower abdominopelvic cavity and pass through the abdominal wall into the scrotum.
- Descent is stimulated by testosterone
- The testes are attached are attached by a fibromuscular cord called the gubernaculum that guides the testes downward.
What is the Tunica Albuginea?
The outer wall of the Testes
– Tough, fibrous capsule surrounding each testis.
– Penetrates testis to divide it into lobules
Explain what structure(s) are after the Lobules of the Testes.
Within lobules are seminiferous tubules
* The seminiferous tubules contain two cell types:
– Sustentacular cells: Non-dividing support cells
– Germ cells: Replicate and develop into sperm cells
The interstitial spaces between the seminiferous tubules are filled with interstitial cells, called Leydig cells, which secrete testosterone.
Explain what structure(s) are after the Seminiferous Tubules of the Testes.
Seminiferous tubules unite to form a tubular network called the rete testis which forms efferent ductules and finally the epididymis.
- Both the rete testis and efferent ductules are lined with ciliated epithelium to help move sperm cells out of the testes
Explain the Epididymis
(contains a head, body and tail)
– Emerges from the top of each testis and runs along the posterior surface and then curves to course upwards and becomes the vas deferens
– Stores sperm cells until they mature and cable of being motile
– Takes 12-16 days for sperm to travel through the epididymis and appear in the ejaculate
Explain the Vas Deferens
– Muscular tubes that emerge from the tail of the epididymis. Has a smooth muscle wall that’s capable of peristalsis (to move sperm cells)
- It enters the abdominal cavity where it is enlarged to form the ampulla.
- Then continues a short distance and converges into the ejaculatory duct.
Explain the Ejaculatory Duct.
– Joining of vas deferens and seminal vesicle (sac-shaped gland)
– Ends at the urethra within the prostate gland
Explain the function and orientation of the Urethra of the male reproductive system.
It extends from the urinary bladder to the distal end of the penis. It functions as a passageway for urine and male reproductive fluids. It’s divided into three parts:
- Prostatic urethra
- Membranous urethra
- Spongy (Penile) urethra
Explain the 3 parts of the Urethra of the male reproductive system.
Prostatic urethra:
- Proximal part, surrounded by the prostate gland
Membranous urethra:
- Shortest part, extends through the perineum
Spongy (Penile) urethra
- Longest part, many small urethral glands empty into the spongy urethra
Explain Seminal Vesicles.
(Accessory Glands)
It produces 60% of seminal fluid.
- Secretes fructose, and prostaglandins, which nourish the sperm cells as they pass the Urethra
Prostaglandins help with the movement of the sperm cells once they enter the female reproductive system.
- Produce fibrinogen which helps clot seminal fluid.
Explain Prostate Glands.
(Accessory Glands)
It produces 30% of seminal fluid
- It neutralizes acids
- Produce fibrinogen which helps clot seminal fluid
- Prevents male UTI’s
Explain Bulbourethral Glands.
(Accessory Glands)
Produces mucous-like secretion that
occurs just before ejaculation.
- It’s released in response to sexual
stimulation to lubricate the end of the penis
Explain what Semen is.
Secretions of all three accessory glands plus sperm cells are referred to as semen.
- Once they are ejected into the female reproductive system, they become motile