Lecture 18 - Male Reproduction Flashcards
Function of the male reproductive anatomy
- produce and deliver gametes to the female reproductive system
What is the scrotum?
2 lobed pouch
- divided into 2 segments by the scrotal septum
- provides protection and support
- thermoregulation
Tunica Dartos
Smooth muscle lining the scrotum
- contracts to draw tested close OR relaxes to allow testes to be further away from the body
Testes
Paired organ
- Site of spermatogenesis and androgen (testosterone) production
- continual production of sperm throughout the animal’s life following puberty
- located outside the body cavity inside the scrotum
Where does Spermatogenesis take place?
The seminiferous tubules
What is spermatogenesis?
Mitosis and Meiosis of male gametes
A continuous process to ensure reproductive readiness
When does Spermatogenesis take place?
During the breeding season or constitutively
Why does Spermatogenesis take place?
To produce a continuous supply of mature male gametes
How does Spermatogenesis take place?
Sertoli cells, leydig cells, blood-testis barrier
What are Sertoli cells?
“Nurse cells”, FSH-receptors, convert testosterone to estrogen, secrete inhibin for negative feedback of FSH
Leydig cells
Interstitial cells (outside of the seminiferous tubules) that produce testosterone in response to LH secretion
What is the Blood-testis barrier?
Prevents immunologic destruction of the developing germ cells (haploid)
What is Spermitogenesis?
Differentiation phase in which sperm undergo morphological transformation from a round spermatic into a mature spermatozoon with a tail
What is Spermiation
Release of mature spermatozoa into the lumen of the seminiferous tubule
What are the hormones of the male reproductive system?
Hypothalamus (GnRH) -> Anterior pituitary (FSH and LH) -> Seritoli and Leydig cells -> inhibin, spermatogenesis
What are the parts of a spermatozoon?
Head (nucleus)
Midpiece (mitochondria)
Tail (flagellum)
What are the parts of the epididymis?
Head (Caput)
Body ( corpus)
Tail (cauda)
What are the 4 functions of the epididymis?
Transport
Storage
Concentration
Maturation
What are some details about the ductus deferens?
Transport sperm from the epididymis
Facilitated by contractions of smooth muscle
Join the urethra near the opening of the bladder
Spermatic cord
Arteries and veins (paniniform plexus)
Nerves
Connective tissue
Muscle (cremaster)
Ductus deferens
Functions - physical support for testes, temperature regulation
What are the physical functions of thermoregulation?
Cremaster muscle and tunica dartoc
Panpiniform plexus
- countercurrent blood supply cooler Venus blood leading to the testis cools warm arterial blood entering war material blood entering the tested
What are the accessory sex glands?
Ampullae, vesicular glands, prostate gland, bulbourethral glands
What do the secretions from the accessory sex glands include?
-buffers, nutrients, inorganic ions for motility and fertility
What is the placement and function of the accessory sex glands?
Located along the pelvic portion of the urethra
Create the liquid, non-cellular portion of semen
What is the penis?
Male organ of copulation
Deposits semen into vagina or cervix of the female
What are the parts of the Penis?
Glans ( sensory nerves and structure complementary to the cervix)
Body (main portion)
Root (2 curve which attach to the ischial arch of pelvis