Male Anatomy Flashcards
What is the spermatic cord and what is the purpose?
connects testis to body, suspends testis in scrotum
What is the scrotum and the function?
Scrotum is the skin surrounding testis, purpose is to surround/support/ protect and thermoregulate
What are the 4 major components of the scrotum?
epidermis, tunica dartos, scrotal fascia, parietal tunica vaginalis
What are the 2 parts of the scrotum that play a role in testis thermoregulation?
epidermis: allows for evaporate heat cooling
tunica dartos: smooth muscle, that draws testes close to abdomen or relaxes “pushes”
cremaster muscle: pulls closer for short term heat conservation
name the layers consisting the testicular capsule, starting from the inner most compartment outward
tunica albuginea, visceral vaginal tunica, vaginal cavity, parietal tunica vaginalis, scrotal fascia, tunica dartos, scrotal skin
explain the process of thermoregulation by scrotum
- uses evaporative heat transfer/ sweating (regulates scrotal sweating)
- thermo sensor via sympathetic nerves in the skin (regulates respiratory rate)
when the male has an increase in scrotum/body temp, there will be a increase in RR, due to the neural pathway starting in the scrotum and terminating in brain.
Why is thermoregulation important for the testes?
Cooling of testes is vital for spermatogenesis, although constant cooling is not necessary. This reflex pathway that results in panting/sweating is not activated until the scrotum temp reaches about 39 C.
DNA in sperm is damaged by heat and that eggs fertilized by these sperms have a low probability of surviving.
What is another way of testicular cooling involving the spermatic cord?
pampiniform plexus and counter current heat exchange
efficient testicular cooling requires scrotal cooling occurs so venous blood in testicle can be cooled. only after the venous blood is cooled can the vascular countercurrent heat exchange function properly.
Describe the counter current heat exchange process
the pampiniform plexus is a venous network that eventually forms a single vein that drains into the caudal vena cava.
the relationship w/ the testicular artery and plexus (finger- like wrappings wrapping around artery) allows close proximity for heat exchange
39 C-34 C, drop in temperature because the blood temp needs to be lower for sperm. Blood is reheated through process, re- entering the body
What is the primary reproductive organ in males and what are the major functions?
testis, main function: spermatozoa, hormones/protein, fluids
What is the fluid that contains products synthesized by Sertoli cells?
rete fluid
What are the 4 major components of the testes?
testicular capsule, parenchyma, mediastinum, seminiferous tubules
What makes up the testicular capsule and what is the purpose of these structures?
- Visceral tunica vaginalis: connective tissue
- Tunica albuginea: dense white connective tissue. Encloses testis and sends finger like projections into the parenchyma
What is the parenchyma, where is it found and what does it make?
parenchyma is found in the testis, it is the major cellular mass of the testis, spermiogenesis and hormones are take place/made here.
What makes up the parenchyma and how are they separated?
TUBULAR COMPONENT
1. seminiferous tubules: sperm is made
2. interstitial cells of Leydig
INTERSITIAL COMPONENT
1. blood vessels
2. lymphatic vessels
3. connective tissue
What is the blood teste barrier and what is the importance? Name the cell and junction that is important.
prevents immunologic destruction of developing germ cells
- the tight junctions between Sertoli cells serve as the second barrier against immune cells and immunoglobins
-peritubular cells surrounding the seminiferous tubule and Sertoli cell complexes the barrier
What is the mediastinum and what is the importance?
the central connective tissue core of the testis
- dense connective tissue of the mediastinum helps prevent compression of the rete tubules
-spermatozoa and fluid from seminiferous tubules moves freely from the testis
What is the order of layers within the testes?
Parenchyma to tubular compartment to seminiferous tubules
What is the tubular component, importance and compartments?
seminiferous tubules, end joins rete tubules (tiny channels through which spermatozoa are transported from the testis)
- tubular compartments consists of
1. seminiferous epithelium
2. Sertoli cells
3. developing germ and peritubular cells
Describe the loops of the seminiferous tubules and where does spermatogenesis takes place?
each loop of the semini. tubule is comprised of a convoluted portion (tubulus contortus) and a straight portion (rectus)
- spermatogenesis takes place mainly in the tubulus contortus