Lecture 4 Flashcards
Function ampulla
Pre-ejaculatory sperm reservoir
Function seminal vesicles
bulk of seminal fluid
Function prostate gland
sugars for motility
Function of the bulbourethral gland
coagulator secretions
What is the function of the spermatic cord (3)
- provides vascular, lymphatic and neural connections to the testis and scrotum
- Houses the cremaster muscle
- Provides a heat exchanger
What is the temperature required for spermatogenesis
4-6 degrees lower than body temperature
How is heat exchange maintained in the testis (3)
- Pampiniform plexus
- Counter current exchange of heat from arterial to venous blood occurs
- Contraction of the cremaster muscle has a pumping effect on the pampiniform plexus to accelerate blood-flow to/from the testis
What is the function of the scrotum (3)
- Protects the testes and epididymis
- Acts as a thermosensor
- Allows evaporative heat transfer
What helps reduce testicular temperature
Increased respiratory rate
Appearance of the dartos muscle
mesh-like smooth muscle layer beneath the scrotal skin
Dartos muscle: what does the degree of contraction depend on
Temperature
What happens to the testical in cold weather
Dartos muscle contracts and the testicle is brought closer to the body for warmth
What is the parenchyma made up of
siminiferous tubules, Leydig cells, capillaries, lymphatic vessels, connective tissue
What is the mediastinum made of
rete tubules –> connect to efferent ducts and caput (head) epididymis
What are the products of the testis (3)
- Spermatozoa
- Hormones and proteins
- Fluids
3 compartments of development of the spermatozoa
- Basal compartment
- Deep adluminal compartment
- Peripheral adluminal compartment
Explain the basal compartment
Spermatogonia devie to form more spermatogonia and primary spermatocytes
Explain the deep adluminal compartment
Primary spermatocytes move through ‘tight junctions’ of adjacent Steroli cells then divide to form secondary spermatocytes and round spermatids
Explain the peripheral adluminal compartment
Spermatids undergo elongation and maturation (spermatogenesis)
How is the Blood-Testis barrier formed
By tight junction between adjacent Sertoli cells
What does the blood-testis barrier prevent
‘naïve’ immune system from mounting a response to ‘foreign’ spermatozoa
What does the blood-testis barrier control
Composition of luminal fluid
What are the 3 sequential phases of spermatogenesis
- Mitotic proliferation
- Meiotic division
- Cytodifferentiation
What occurs in proliferation
Spermatogonia undergo several mitotic divisions
