Section One Flashcards
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
Describe the seminal vesicles.
-one of the accessory glands
-there are 2
-located on the posterior surface of the bladder, in front of the rectum
-provides fluids and nutrients to the ejaculate and makes up 60% of the volume of semen
Describe the prostate gland.
-one of the accessory glands
-size of a walnut
-located beneath the bladder
-consists of tubular glands embedded in a mass of smooth muscle and connective tissue
-produces and secretes sugars and enzymes
-accounts for 33% of the volume of seminal fluid
Describe the bulbourethral glands.
-one of the accessory glands
-two pea sized glands
-immediately below the prostate and at the base of the penis
-secrete a thick, clear, alkaine mucus that drains into the penile urethra
-secretion is released before ejaculation to. neurtralize the traces of acidic urine into the urethra and to lubricate the urethra and penis
Why are the nutrients the accessory glands provide to the sperm added?
Sperm requires a high amount of nutrients to produce energy to travel through the male reproductive system, and then through the female reproductive system for reproduction. The alkaline secretions neutralize the acidic environment of the vagina.
Describe the pathway of sperm.
Sperm is produced in the seminiferous tubules of the tested and transported through a series of ducts before exiting the body. From the testes, sperm passes through the epididymis, vas deferens, ejaculatory duct, and urethra. Along its course through the male duct system fluid is secreted from glands that contribute to the volume of semen.
What is the function of the penis and what are the 3 parts?
*has both urinary and reproductive functions as it serves as a conduit for the pathway of sperm and urine.
The 3 parts are:
- Root of penis
- Body of Penis
- Glans of Penis
What is the function and location of the root of the penis?
It is the fixed portion that attaches the penis to the ishium (pelvic bone).
What is the function and location of the body of the penis?
it is tubular, moveable portion of the penis that consists of three cylinders of erectile tissues and contains the urethra.
What is the function and location of the glans of the penis?
it is the expanded distal end (the tip of the penis), and this is what contains the external urethral opening.
How many types of tissue does the penis have and what are their names?
There are 2 different erectile tissues.
- Corpora Cavernosa
- Corpus Spongiosum
What is the Corpora Cavernosa? Provide Details.
It is the two erectile cylinders on the dorsal surface of the penis, which makes up most of the mass of the penis.
The proximal portions are known as the crura (singular it is the crus) and are attached to the bony pelvis by muscles.
What is the corpus spongiosum? Provide details.
this cylinder contains the urethra and expands distally to form the glands of the penis. the proximal end is enlarged and it is called the bulb of the penis.
How does a vasectomy prevent pregnancy?
The cutting of the vas deferens would stop the sperm from travelling from the epididymis to the urethra, and as a result, the sperm would not be able to leave the male reproductive system to cause fertilization in the female’s body.
