Lecture 68 - Male reproductive anatomy

Question 1

What is the main difference between the male and female perineal membrane and deep perineal pouch?

Answer 1

There is no vaginal opening in males (midline fusion event during development) - there is only a urethral opening.

Question 2

What is the difference between the male and female external urogenital sphincters?

Answer 2

There are no vaginal sphincters in the male - only the urethral sphincter.

Question 3

What is the role of the urethral sphincter?

Answer 3

It maintains urinary continence

Question 4

What structure, contained within the testes, produces spermatozoa?

Answer 4

The seminiferous tubules.

Question 5

Where are the immature spermatozoa collected?

Answer 5

Rete testes

Question 6

Where are the spermatozoa stored and matured?

Answer 6

Epididymus

Question 7

What is the layer of thick connective tissue surrounds the seminiferous tubules?

Answer 7

The tunica albuginea

Question 8

What does it mean for a spermatozoa to ‘mature’?

Answer 8

Acquire the abilities to move and to fertilize an ovum.

Question 9

What happens to the sperm if ejaculation does not occur?

Answer 9

They are reabsorbed in the epididymus and the components are recycled.

Question 10

How many seminiferous tubules are there?

Answer 10

~400-600 in each teste

Question 11

Where about in the abdominopelvic cavity do the ovaries/testes develop?

Answer 11

High up on the posterior abdominal wall, beneath the kidneys

Question 12

By 7 months gestation the testes have descended towards what structure in the anterior abdominal wall?

Answer 12

The inguinal canal.

Question 13

By what time in gestation have the testes externalized?

Answer 13

About 9 months, usually just before birth

Question 14

The descent of the testes during development ‘drags’ what structures from the posterior abdominal wall?

Answer 14

Blood vessels, nerves, ducts (ie, vas deferens) and layers of the abdominal wall

Question 15

What is the spermatic cord?

Answer 15

The cord-like structure in males formed by the vas deferens and surrounding tissue that run from the deep inguinal ring down to each testicle.

Question 16

What is the vas deferens?

Answer 16

Muscular duct that transports spermatozoa to the ejaculatory duct

Question 17

What is the wall of the vas deferens made of?

Answer 17

Smooth muscle

Question 18

The vas deferens penetrates the anterior abdominal wall through what structure?

Answer 18

The inguinal canal.

Question 19

Each vas deferens descends along what part of the pelvic cavity to meet the ducts of the seminal vesicle?

Answer 19

The lateral wall

Question 20

What is the ejaculatory duct comprised of?

Answer 20

Duct of seminal vesicle and the vas deferens

Question 21

Describe the path of descent of the vas deferens from the top of the pelvic cavity to the ejaculatory duct.

Answer 21

Lateral to the bladder and posterior to the prostate gland.

Question 22

Is ejaculation mediate by the sympathetic or parasympathetic nervous system?

Answer 22

Sympathetic

Question 23

What is a vasectomy?

Answer 23

The ligation and/or severing of the vas deferens to prevent the transmission of sperm during ejaculation.

Question 24

There are three accessory glands of the male reproductive system that contribute to the volume of the semen. What are they called?

Answer 24

Seminal vesicle, prostate, bulbourethral glands

Question 25

Where is the seminal vesicle located relative to the bladder?

Answer 25

Along the posterior surface of the bladder

Question 26

The ducts of the seminal vesicles join with the vas deferens to form the ejaculatory duct. Which other accessory gland does the ejaculatory duct empty in to?

Answer 26

The prostate

Question 27

What does the seminal vesicles contribute to the volume of the semen?

Answer 27

Fructose (for ENERGY!!!) and a coagulating agent

Question 28

Where are the bulbourethral glands located?

Answer 28

In the deep perineal pouch

Question 29

What is the role of the bulbourethral glands?

Answer 29

Secretes a mucous-like volume that lubricates the urethra, ie it forms the pre-ejaculate

Question 30

Describe the location of the prostate relative to adjacent structures.

Answer 30

Inferior to the bladder, anterior to the rectum, Superior to the perineal membrane, surrounds the urethra

Question 31

The prostate is comprised of approximately how many individual glands?

Answer 31

30-40

Question 32

The ducts of all of the individual glands of the prostate open into what part of the urethra?

Answer 32

The prostatic urethra

Question 33

The prostate provide approximately what % of the volume of the ejaculate?

Answer 33

~20%

Question 34

What is one of the roles of the secretion of the prostate?

Answer 34

Activation of the sperm

Question 35

Benign prostatic hypertrophy is enlargement of which part of the prostate?

Answer 35

The central portion

Question 36

What is the primary symptom of benign prostatic hypertrophy? Why?

Answer 36

Reduced ability to urinate because of compression of the urethra.

Question 37

What is the easiest way to detect benign prostatic hypertrophy? Why?

Answer 37

DRE - digital rectal examination.

Question 38

Prostatic cancer affects the thickness of what portion of the prostate?

Answer 38

Trick question: affects the thickness of the entire prostate

Question 39

Upon DRE, what is the difference between a prostate with benign hypertrophy and one with cancer?

Answer 39

Benign hypertrophy: prostate will feel 'bulky'; | Cancer: prostate will feel 'rock hard' and can feel vessels.

Question 40

What pelvic structures provide attachments for the external male genitalia?

Answer 40

Perineal membrane and pubic arch

Question 41

The penis is made out of two separate erectile tissues. What are they?

Answer 41

Two corpora caversona (dorsal) and a single corpus spongiosum (ventral, medial)

Question 42

The glans penis is an extension of which of the erectile tissue?

Answer 42

Corpus spongiosum

Question 43

The urethra penetrates the perineal membrane and enters which of the erectile tissues of the penis?

Answer 43

Corpus spongiosum

Question 44

Is erection mediated by the sympathetic nervous system or the parasympathetic nervous system? How?

Answer 44

The parasympathetic nervous system dilates blood vessels, which engorges the tissues of the penis.

Question 45

Which two muscles, when they contract, pump blood from the root of the penis into the body during erection?

Answer 45

Ischiocavernosus and bulbospongiosus muscles

Question 46

Describe the body of the penis.

Answer 46

Pendulous and surrounded by skin

Question 47

The scrotum is a homologue of what structure in the female reproductive system?

Answer 47

The labia majora

Question 48

What is the raphe?

Answer 48

The line down the middle of the scrotum that delineates the midline fusion of the labia major during development.

Question 49

What is the anatomical name of the foreskin?

Answer 49

Prepuce

Question 50

The prepuce attaches to the glands penis via what structure?

Answer 50

The frenulum