Lab 11: Male Reproductive

Question 1

Describe the location of the ductus (vas) deferens

Answer 1

Low, posterior facing knob on the seminal vesicles

Question 2

What does the ejaculatory duct empty into?

Answer 2

The prostatic urethra

Question 3

Where is the prostate gland?

Answer 3

Below the bladder

Question 4

Where is the membranous urethra?

Answer 4

Inside the urogenital diaphragm below the prostatic urethra

Question 5

Where is the urogenital diaphragm?

Answer 5

A red flat muscle between the prostate and penis

Question 6

Where is the corpus spongiousum of the penis?

Answer 6

It’s a small muscle in front of and behind the urethra

Question 7

Where is the corpus cavernosum of the penis?

Answer 7

A large muscle in front of the urethra and corpus spongiousum

Question 8

Where is the glans of the penis?

Answer 8

The head

Question 9

What is the prepuce?

Answer 9

The foreskin on the glans of the penis

Question 10

Why do the testes need to be outside the abdominopelvic cavity?

Answer 10

To keep their temperature low enough to produce sperm (below core temp)

Question 11

Outside of the seminiferous tubules of the testes you can find interstitial, or ___________ cells that produce testosterone

Answer 11

Leydig

Question 12

1) What are the stem cells that produce sperm called?
2) When are they developed, and when are they active?
3) What happens when a spermatogonia divides (what are the daughter cells)?
4) Where are spermatogonia found?

Answer 12

1) Spermatogonia
2) In the embryo, but are dormant until puberty
3) One of the daughter cells remains a stem cell, the other differentiates into a primary spermatocyte
4) On the outer rim of the seminiferous tubules

Question 13

What two things can be found on the rim of the seminiferous tubules?

Answer 13

1) Spermatogonia
2) Sustenocytes (aka Sertoli cells or nurse cells)

Question 14

What do sustenocytes (aka Sertoli cells or nurse cells) do?

Answer 14

Protect and provide nutrients to the dividing cells (spermatogonia)

Question 15

1) When primary spermatocytes divide, where do the daughter cells go?
2) Are the sperm in the testes mature?
3) How long does it take a primary sperm to mature?
4) How many sperm are made a day?

Answer 15

1) Towards the lumen of the seminiferous tubules
2) No, they’re non-swimmers
3) ~70 days
4) 400 million/ day

Question 16

List the steps of sperm production and division (7)

Answer 16

1) Spermatogonium (diploid)
2) Primary spermatocyte (diploid)
3) Meiosis I
4) Secondary spermatocytes (haploid)
5) Meiosis II
6) Spermatids (haploid)
7) Spermatozoa

Question 17

1) What forms the spermatic cord?
2) What is the spermatic cord?

Answer 17

1) Nerves, blood vessels, lymphatic vessels, etc.
2) What the testes are attached to as they move into the scrotum of a fetus

Question 18

1) Where do the testes develop in fetuses?
2) When do testes descend into the scrotum?

Answer 18

1) Just below the kidneys in the abdominal cavity
2) Around 7 months gestation

Question 19

What is the name of the cell division spermatogonia use?

Answer 19

Mitosis

Question 20

1) What hormone stimulates interstitial (Leydig) cells?
2) What hormone do they produce in response?

Answer 20

1) LH
2) Testosterone

Question 21

What are spermatogonia also called? What can they be the source of?

Answer 21

Germ cells; testicular cancer

Question 22

When does ‘crossing-over’ occur?

Answer 22

During Prophase I (primary spermatocytes into secondary spermatocytes)

Question 23

1) What is the result of meiosis I?
2) What is the result of meiosis II?

Answer 23

1) 2 haploid double-stranded daughter cells (secondary spermatocytes)
2) 4 viable haploid spermatids (single stranded)

Question 24

Where does differentiation into spermatozoa happen?

Answer 24

In the epididymis

Question 25

1) How many chromosomes are in the nucleus of a sperm?
2) What are the 3 parts of a sperm?
3) What is the acrosome of a sperm?

Answer 25

1) 23
2) Head, midpiece of tail, tail
3) A layer around the head of the sperm, has lots of lysosomes

Question 26

1) What can be found in the head of a sperm?
2) What can be found in the midpiece of the tail of a sperm?

Answer 26

1) The nucleus
2) Mitochondria

Question 27

What 4 things contribute to the production of semen? List them from least to most sperm produced.

Answer 27

1) Sperm: 10%
2) Bulbourethral (Cowper’s) gland: trace
3) Prostate gland: 30%
4) Seminal vesicles: 60%

Question 28

1) What is the fluid secreted from the seminal vesicles rich in? Why?
2) How many seminal vesicles are there? Are they anterior or posterior to the bladder?

Answer 28

1) Fructose; as an energy source
2) 2; posterior to urinary bladder

Question 29

1) Is the fluid secreted from the prostatic gland acidic or basic? Why?
2) Is the fluid secreted from the bulbourethral (Cowper’s) glands acidic or basic? Where does it secrete it?

Answer 29

1) Slightly acidic due to the citric acid it releases
2) Basic mucus into the penile urethra

Question 30

1) The 2 dorsal columns of the penis are called the _______ ______________.
2) The one ventral column is called the ___________ __________.

Answer 30

1) Corpus cavernosum
2) Corpus spongiosum

Question 31

The distal end of the __________ __________ to form the glans penis. This area is covered by the ___________.

Answer 31

corpus spongiosum; prepuce (foreskin)

Question 32

1) The penis consists of how many columns of erectile tissue? Name them.
2) Which allows for penetration?
3) Which keeps the urethra open?

Answer 32

1) 3; two corpus cavernosum and one corpus spongiosum
2) Corpus cavernosum
3) Corpus spongiosum

Question 33

Trace the path of sperm from the seminiferous tubules out (7 steps)

Answer 33

1) Seminiferous tubules
2) Epididymis
3) Ductus (vas) deferens
4) Ejaculatory duct
5) Prostatic urethra
6) Membranous urethra
7) Spongy (penile) urethra

Question 34

1) What happens in the seminiferous tubules?
2) What happens in the epididymis?

Answer 34

1) Meiosis occurs and sperm is produced
2) Sperm mature and can be stored for several months

Question 35

1) Where is the ductus (vas) deferens
2) How is sperm propelled through it?

Answer 35

1) Runs up through the inguinal canal and enters the pelvic cavity and loops to the posterior portion of the urinary bladder.
2) Sperm is propelled through this tube by peristaltic contractions during ejaculation.

Question 36

What two things merge to form the ejaculatory duct

Answer 36

Ductus (vas) deferens joins a seminal vesicle

Question 37

1) Define the prostatic urethra
2) Define the membranous urethra
3) Define the spongy (penile) urethra

Answer 37

1) Prostatic: multiple ducts from the prostate gland also dump into the urethra during ejaculation
2) Membranous: part of the urethra that passes through the urogenital diaphragm
3) Spongy: part of the urethra found in the penis.

Question 38

Near the beginning of the spongy urethra, the ducts of what glands empty into the urethra?

Answer 38

Two bulbourethral glands