Male Reproductive Tract

Question 1

What are the testes

Answer 1

-Ovoid shapes

Responsible for the production and development of:
-sperm
-testosterone

Question 2

Where do the testes lie ?

Answer 2

Within the scrotum
Lined internally by muscle

Suspended from the abdominal cavity

Question 3

Where is pampiniform plexus ?

Answer 3

At the cranial pole of the testes = where the incoming artery and the outflow is vein intertwine

Question 4

What are seminiferous tubules ?

Answer 4

Long and convoluted, lined by spermatozoa and Sertoli cells.

Question 5

What does spermatogonia produce ?

Answer 5

Spermatozoa
(Sertoli cells nourish the spermatogonia)

Question 6

What is the epididymis?

Answer 6

-cylindrical organ applied closely to the long axis of the testicle.

-the seminiferous tubules empty via the efferent ducts into the epididymis

Question 7

What is the ductus deferens ?

Answer 7

It runs up the spermatic cord and enters the abdomen through the inguinal canal.

Widens into the ampullae and then empties unto the urethra.

Question 8

Describe the penis

Answer 8

Mainly cylindrical and extends from the ischial arch of the pelvis to about the umbilicus.

Can be muscular (stallion, dog, cat)
Fibro-elastic (bull, ram)

Question 9

Where does the penis lie?

Answer 9

Within a sheath at its external end.
Covered by the prepuce.

Question 10

What way does the penis in a cat and camel face?

Answer 10

Posterior facing
(Backwards)

Question 11

What erectile tissue does the penis consist of?

Answer 11

Corpus cavernosum - body of penis

Corpus spongiosum - surrounds urethra (holds urethra open)

Question 12

What is an erection?

Answer 12

Primarily controlled by the parasympathetic nervous system
= dialation of arteries (blood fills cavernous tissue)

= contraction of small veins and muscular occlusion of large dorsal vein (restricts venous return)

Question 13

What is ejaculation

Answer 13

Controlled by the sympathetic nervous system

=rhythmic contractions of the accessory glands and the urethra.

Question 14

What are the accessory reproductive organs ?

Answer 14

-seminal vesicles

-ampullae

-prostate

-bulbs-urethral glands

(They contribute to the preparation of the ejaculate by suspending the sperm in their secretions)

Question 15

What are the ampullae ?

Answer 15

Present in the terminal portions of the ductus deferens in the stallion, bull, ram and dog.
=glandular
=storage area (except boar)

Question 16

What are the seminal vesicles ?

Answer 16

-vesicular
-paired (one/vas deferens)
-lie adjacent to the neck of the bladder, and empty into the urethra (via ductus deferens)
-not present in the dog
-add fluid and nutrients to the semen (eg - fructose)

Question 17

What is prostrate ?

Answer 17

• firm gland that surrounds the urethra

-large in the dog
-produces alkali secretion (pH 6.0 - optimum for sperm activity)
-acts as buffer
-produces characteristic odour

Question 18

What is bulbs-urethral glands

Answer 18

-lie between the anus and the urethra

-not present in the dog (but v large in the boar)

-secrete thick mucous to assist in lubrication at coitus

-may secrete fluid prior to ejaculation

-high volume gel secretion in boars.

Question 19

What is spermatogenesis?

Answer 19

= spermatocytogenesis = spermiogenesis

Question 20

What is spermatocytogenesis ?

Answer 20

Cell division of spermatogonia

Question 21

What is spermiogenesis ?

Answer 21

Production of sperm

Question 22

How do spermatids develop ?

Answer 22

• acrosome

-head (contains DNA)

-midpiece (contains the mitochondria)

-tail (flagellum)