Section One Flashcards
(37 cards)
What is a gamete cell?
An organism’s reproductive cell
Describe the testes.
-site of sperm production and development
-2 of them
-oval shaped
-4/5 cm in length, 2.5/3 cm wide
What are the 2 tissues the testes are protected/covered by?
- Tunica Vaginalis: the outer protective covering
- Tunica Albuginea: the inner fibrous coat. Extensions from the tucina albuginea penetrate into the testis, dividing it into 250-300 compartments known as lobules. And each lobules contains up to 4 thin and elongated seminiferous tubules.
What are seminiferous tubules?
- They are located within the testes
-They are tightly coiled seminiferous tubules
-they are the sperm production factories
-Each testes has around 600-1000 seminiferous tubules within their lobules
-each tubule around 80cm when uncoiled
-between the loose connective tissue between the tubules, Leydig cells are found which produce and secrete testosterone.
What are sperm?
The gametes of the male reproductive system, and they carry the parental genetic information.
Can carry x or y.
Describe the head of the sperm.
-Flat with an oval shape
-Contains the nucleus
-The nucleus contains either and x or y chromosome
-Has a acrosomal cap
What is the role of the acrosomal cap of the head of the sperm?
Contains enzymes that are release prior to fertilization to help the sperm penetrate the layers of the egg.
What is the role of the neck of the sperm?
connects the head to the midpiece.
What is the role of the midpiece of the sperm?
It is a continuation of the neck, with a mitochondrial collar that helps produce energy.
What is the role of the tail of the sperm?
Also known as the flagellum, is the source of movement for the sperm.
How many regions of the sperm are there are what are their names?
There are 4:
-head
-neck
-midpiece
-tail
What is the scrotum? Where is it located?
It is a sac of skin and fascia surrounding the testes. IT is derived from the anterior abdominal wall and resides outside of the abdominopelvic cavity.
How many muscles are in the scrotum? What do they work together to do and what are there names?
There are 2 muscles: Dartos muscle and cremaster muscle.
*they work together to control the temperature of the testes
Describe the Dartos muscle.
-located superficially in the skin of the scrotum
-responsible for the wrinkly appearance of the scrotal sac
-helps to regulate temperature by altering the exposed surface area of the scrotum
Describe the cremaster muscle.
-one of the muscles of the scrotum
-found deep within the scrotal wall
-reflexively contracts in a cold environment, drawing the testes superior in the scrotum (closer to the body wall so they can absorb heat)
How must the sperm travel to pass outside the body?
through a duct system. the right and left testes each have their own duct systems.
What are the structure of the male duct system?
- Epididymis
-Vas deferens
-Urethra
What is the epididymis? Where is it located, the regions of it, etc?
-Part of the male duct system
-This is the first portion of the male duct system
-Lies on the superior and posterior border of each testis
-shaped like a comma
-There are 3 components: head, body, tail.
Name the 3 parts of the head of the epididymis and their role.
- Head: contains and receives sperm from the seminiferous tubules.
- Body: lies on the posterior lateral border of the testis and contains the highly coiled duct of the epididymis
- Tail: This is where sperm are stored prior to ejaculation. It is located near the inferior border of the testis. The coiling of the duct has diminished and the tube reverses its direction and ascends into the vas deferens.
What are the ducts of the epididymis lined with?
Pseudo-stratified columnar epithelium.
What is the Vas Deferens (Ductus Deferens)? Detail.
-Second portion of the male duct system
-stores and transports sperm from the epididymis to the urethra
-it is like with pseudostratified columnar epithelium containing sterocilia
-has a small lumen, but a thick muscularis composed of layers of smooth muscle (this thick muscularis helps propel sperm through the vas deferens)
What are the structures associated with the vas deferens? And what are their functions?
- Ampulla of Vas Deferens: the expanded distal portion of the vas deferens.
- Ejaculatory Duct: The ampulla of the vas deferens and the duct of the seminal vesicle join to form this duct. Accessory glands of the male reproductive system that secretes nutritive fluid for the sperm.
Describe the urethra?
It is part of the urinary system and is also the terminal portion of the male duct system, and transports sperm out of the body. It contains 3 sections:
- Prostatic urethra
-membranous urethra
-penile urethra
What are the 3 accessory glands and what is their general function?
*they nourish the sperm as they travel through the duct system
- Seminal vesicle
- Prostate gland
- Bulbourethral glands