Male Reproductive System

Question 1

Name the main components of the male reproductive system?

Answer 1

Male primary sex organs (Gonads):
Testes

Accessory structures:
Scrotum
Epididymis
Ductus deferens
Ejaculatory duct
Prostate gland
Seminal vesicles
Bulbourethral glands
Penis

Question 2

Identify the main components of the male reproductive system?

Answer 2

Question 3

Explain the basic functions of the male reproductive system?

Answer 3

Production of gametes:
The testes produce sperm.

Production of sex hormone:
The testes produce androgens (testosterone is the most common).

Facilitation of fertilisation:
Sperm travel towards the ovulated oocyte to fertilise it.

Question 4

What is the primary germ layer that the male reproductive system is derived from?

Answer 4

The mesoderm

Question 5

Briefly describe the embryological development of the testes?

Answer 5

1. 5th week of development: paired genital (gonadal) ridges form from the mesoderm.
2. During development, the descend descend to the scrotum by being guided by the gubernaculum (a thin band of connective tissue) passing through the inguinal canal.
3. Gubernaculum forms the scotal ligament which tethers each testis to the scrotum internally.

Question 6

Describe the location and function of the scrotum?

Answer 6

Location:
Sits outside the trunk of the body.

Function:
Provides the cooler environment needed for normal sperm production.

Question 7

Describe the gross anatomy of the scrotum?

Answer 7

–> The cutaneous sac that the testes are located in.
–> Contains two muscles (the dartos muscle & the cremaster muscle).

Question 8

Describe the location and function of the spermatic cord?

Answer 8

Location:
Travels through the inguinal canal.

Function:
Carries the ductus deferens, blood vessels, nerves and lymphatic vessels between the testes and the abdominopelvic cavity.

Question 9

What are the muscles that respond to changes in temperature to keep the testes at the ideal temperature for sperm production?

Identify them?

Answer 9

The dartos muscle
The cremaster muscle

Question 10

What are the functions of the dartos muscle & cremaster muscle?

Answer 10

Dartos muscle:
When the testes are exposed to cold temperatures, the dartos muscle contracts to wrinkle the scrotal skin and reduce heat loss.
When the testes are exposed to hot temperatures, the dartos muscle relaxes to unwrinkle the scrotal skin and increase heat loss.

Cremaster muscle:
When the testes are exposed to cold temperatures, the cremaster muscle contracts to bring the testes closer to the trunk of the body and conserve heat.
When the testes are exposed to hot temperatures, the cremaster muscle relaxes to allow the testes to move away from the trunk of the body and cool down.

Question 11

Describe the location and function of the testes?

Answer 11

Location:
Within the scrotum.

Function:
To produce the male gametes and sex hormones.

Question 12

Name & identify the external layers of the testes?

Answer 12

Tunica vaginalis (outer visceral & inner parietal layer)
Tunica albuginea

Question 13

Name internal anatomy of the testes?

Answer 13

Each testis is divided into smaller sections called lobules, which contain highly coiled structures called seminiferous tubules.

Question 14

Where is sperm & testosterone produced in the testes?

Answer 14

Sperm = produced in the lobules.
Androgens (including testosterone) = the spaces between the seminiferous tubules.

Question 15

Identify the internal & external anatomy of the testes?

Answer 15

Question 16

Describe the collective function of the epididymis, ductus deferens & ejaculatory duct?

Answer 16

Store and transport sperm.

Question 17

Identify the the epididymis, ductus deferens and ejaculatory duct?

Answer 17

Question 18

Explain the process of ejaculation?

Answer 18

1. Many small ducts in each testis ultimately form a highly coiled duct within a structure called the epididymis.
2. The duct of the epididymis is continuous with the ductus deferens.
3. The ductus deferens unites with the ejaculatory duct.
4. The ejaculatory duct opens into the prostatic urethra, where ejaculation occurs.

Question 19

Describe the location, function and gross anatomy of the epididymis?

Answer 19

Location:
Sits along the posterior surface of each testis.

Function:
The site of sperm storage and maturation.

Gross anatomy:
- A comma-shaped structure.
- Has a head, body and tail.

Question 20

Describe the location of the ductus deferens?

Answer 20

Is continuous with the epididymis and terminates as a dilated part called the ampulla.

Question 21

Describe the location of the ejaculatory duct?

Answer 21

Is continuous with the ampulla and opens into the prostatic urethra.

Question 22

Identify the accessory glands (seminal vesicle, prostate gland & bulbourethral gland)?

Answer 22

Question 23

Describe the collective function of the accessory glands?

Answer 23

To produce secretions that collectively form seminal fluid.

Question 24

When does semen form?

Answer 24

When seminal fluid is combined with sperm during sexual intercourse.

Question 25

What are the functions of seminal fluid?

Answer 25

1. Provide nourishment to the sperm as they travel through the female reproductive tract. 2. Neutralise the acidity of the vagina to protect the sperm.

Question 26

Describe the location, function and gross anatomy of the seminal vesicle?

Answer 26

Location: Located lateral to the ampulla of each ductus deferens on the posterior surface of the urinary bladder. Function: 1. Secrete a viscous, alkaline fluid that is rich in fructose: --> The alkalinity of this fluid neutralises the acidity of the vagina. --> The fructose provides nourishment to the sperm. --> Secretions of the seminal vesicles also contain prostaglandins, that promote dilation of the external of the cervix, allowing the sperm to enter the uterus. Gross anatomy: Paired, elongated glands.

Question 27

Describe the location, function and gross anatomy of the prostate gland?

Answer 27

Location: Directly inferior to the urinary bladder. Function: 1. Secretes a slightly milky fluid that is weakly acidic due to it containing citric acid: --> Important for sperm health. --> The fluid contains an antibacterial agent to fight urinary tract infections in the male. --> The fluid also contains a prostate-specific antigen (PSA) which acts as an enzyme to help liquefy the ejaculated semen once it enters the female reproductive tract. Gross anatomy: Single, walnut-shaped gland.

Question 28

Describe the location, function and gross anatomy of the bulbourethral gland?

Answer 28

Location: Located on either side of the membranous urethra within the urogenital diaphragm. Function: They secrete a clear, viscous fluid into the urethra to lubricate it prior to ejaculation. Gross anatomy: Paired, pea-shaped glands.

Question 29

Describe the function of the penis?

Answer 29

Urination: The urethra carries urine from the bladder to outside the body. Sexual intercourse: The penis is composed of erectile tissue that contains a network of venous spaces that fill with blood during sexual arousal, causing an erection. Ejaculation: Semen is then ejaculated from the penis via the urethra.

Question 30

Name & identify the parts of the penis?

Answer 30

Question 31

Describe the gross anatomy of the glands of the penis?

Answer 31

- Formed by the corpus spongiosum and contains the external urethral orifice. - Covered by a circular fold of skin called the prepuce (foreskin) in an uncircumcised penis.

Question 32

Describe the gross anatomy of the body of the penis?

Answer 32

Composed of three cylindrical masses (a single corpus spongiosum & a paired corpora cavernosa) of erectile tissue that are continuations of the root structures of the penis.

Question 33

Describe the gross anatomy of the root of the penis?

Answer 33

Composed of a single mass of erectile tissue called the bulb of the penis and two elongated masses of erectile tissue called crura.