Male Reproduction

Question 1

Pathway of sperm?

Answer 1

Seminiferous Tubules: sperm production
↓ *First 3 are inside testicles
Straight Duct (tubulus rectus):
↓
Rete Testis: net like structure
↓
Efferent Ducts: leave testicle through
↓
Epidiymis: tightly coiled tube, function is temporary sperm storage site, final maturation. *Outside the testicle
↓
(Ejaculation out into the abdomen)
↓ (or)
Vas Deferens: (2) (thin muscular tube, smooth muscle in the Vas Deferens constricts to move the sperm along back to the abdominal cavity) cutting of the Vas Deferens – (vasectomy) prevents sperm from getting out
↓
Ampulla: (tube like organ) – end of the Vas Deferens
↓accessory glands
1) Seminal Vesicles: (2) adds 60% to semen volume (Ex: Fructose for sperm, to supply food for mitochondria in sperm)
↓
2) Ejaculatory Duct: (2) run through the prostate gland, adds 30% to semen volume, used to neutralize acidic environment in the female reproduction track to allow sperm to get through.
↓ *Prostate Cancer is the third most common cancer in men.
Prostatic Urethra: Prostate gland runs through, so if prostate is growing this can cause issues
Penile / Spongy Urethra:
Membranous Urethra: penetrates the abdominal cavity
↓
3) Bulbourethral Glands: adds 5% to semen volume, serves as a lubricant and to neutralize residual urine in urethra.
*Remaining 5% is sperm

Question 2

What is the counter current exchange?

Answer 2

(Modification of the circulatory system)
Warm blood flowing down the testicular artey loses some of its heat to the cooler blood flowing in the opposite direction

Question 3

Describe the temperature of the testis needed to produce viable sperm?

Answer 3

1. Testis are not located in the abdomial cavity, but in the scrotum for heat dissipation
2. Dartos (smooth muscle) and Cremaster (skeletal muscle from the abdominal cavity)Muscles are used to control heat gain from the floor of the abdominal cavity
3. Counter Current Heat exchange
   * Temp of testis must be 4 degrees F lower than body temp 98.6

Question 4

Describe the Testes?

Answer 4

Scrotum
Tunica Vaginalis- partial lose fitting bag

Tunica albuginea - fibrous connective tissue, protects, white fibrous capsule

Septum - separates septum into lobules to help isolate infections, and reduce damage

Seminiferous tubules - where sperm is produced

Question 5

What are the 2 types of penis erectile tissue?

Answer 5

Crpora Cavernosa

Corpus Spongiosum

Question 6

Corpora Cavernosa?

Answer 6

Top fibrous connective tissue framework, 2 columns (each side) - fills with blood during arousal

Question 7

Corpus Spongiosum?

Answer 7

Single column wrapped around urethra, expands and forms head of penis

Question 8

Prepuce?

Answer 8

Foreskin, continues over glans, often removed by circumcision

Question 9

Describe what is found in the head of Spermatozoon?

Answer 9

Acrosome: Contains enzymes that are later used to penetrate the egg

Nucleus: contains haploid set of condensed, genetically inactive chromosomes

Question 10

Describe what is found in the tail of Spermatozoon?

Answer 10

Midpiece: contains numerous large mitochondria, that produce the ATP for migrating

Rest of flagellum: principal piece, and end piece, makes whiplike motion

Question 11

Describe the descent of the testes?

Answer 11

The testes and spermatic ducts are retroperitoneal .

An extension of the peritoneum called the vaginal process passes through the inguinal and becomes the tunica vaginalis

Question 12

What is the female homologous structure to the glans of the penis of the male?

Answer 12

Clitoris

Question 13

What is meant by homologous?

Answer 13

Structures that have the same developmental origin, but different functions

Question 14

What is the male homologous structure to the labia minor of the female?

Answer 14

Shaft of the penis

Question 15

What is the female homologous structure to the scrotum of the male?

Answer 15

Labia Major