Highison--Male Reproduction Flashcards
What temperature is the scrotum at? How is this achieved?
35 degrees
outside of the central body
countercurrent heat exchange via pampiniform plexus
What are the 2 functions of the testis?
Endocrine Function–Steroidogenesis (Testosterone)
Exocrine Function–Gametogenesis (spermatozoa)
There is a space that separates the outer & the inner sections of the scrotum…what are the layers of the inner section? Outside–>Inside
Space Mesothelial Cells Visceral Layer of Tunica Vaginalis tunica albuginea (CT) tunica vasculosa Seminiferous Tubules
There is a space that separates the outer & the inner sections of the scrotum…what are the layers of the outer section? Outside–>Inside
Epidermis of Scrotum Probably Dermis (skin that contains hair, sebaceous glands, sweat glands) Dartos Muscle Colles' Fascia Parietal Layer of Tunica Vaginalis Mesothelial Cells Space
What are the 2 types of epithelium in seminiferous tubules?
Spermatogenic Epithelium
Sertoli Cells
Starting @ epithelium & going to the outside…what are the layers?
Epithelium
Basement Membrane
CT sheath: w/ blood vessels, lymphatics, myoepithelial cells
What are the cells found in the interstitium b/w the seminiferous tubules?
Interstitial Cells
**Leydig cells–>testosterone
What is the state of seminiferous tubules before puberty?
solid in cross section, not yet the site of spermatogenesis.
Describe spermatogenesis.
occurs in waves in the seminiferous tubules, called cycles, can happen b/c of intercellular bridges
What are the 3 phase of spermatogenesis? How long does this process take in a human?
74 days
Phase I: Spermatocytogenesis
Phase II: Meiosis
Phase III: Spermiogenesis
Which 2 things are needed for testosterone production?
LH & prolactin
Which 2 things are needed for spermatogenesis?
FSH
Testosterone
Where do spermatogonia stem cells come from?
from the yolk sac
Primary spermatocyte goes to ____ _____ via ______. Primary spermatocytes are Haploid or diploid?
Primary spermatocyte goes to secondary spermatocyte via Meiosis I. Diploid.
Secondary Spermatocyte goes to ____ via ____. Secondary spermatocytes are Haploid or Diploid?
Secondary spermatocyte–>spermatids via Meisosis II. Haploid
What does spermiogenesis do?
It turns spermatids–>spermatozoa
**cytodifferentiation phase
What are the 3 morphological phases of spermiogenesis?
Golgi Phase
Cap Phase/Acrosomal Phase
Maturation Phase
In the cap phase/acrosomal phase–>what is formed? Which enzymes are used?
acrosomal cap & acrosome hyaluronidase neuraminidase acid phosphatase proteases
What happens to the cell during the maturation phase?
nucleus is flattened
more mitochondria
elongation of the cell
loss of excess cytoplasm
Describe the mobility of the spermatozoa upon release by seminiferous tubules.
They are immobile.
Once they reach the epididymis they gain motility.
They can’t fertilize until they undergo capacitation in the oviducts. Their glycocalyx is replaced.
T/F All Sertoli cells are continuous.
TRUE, connected by jcnl complex.
Sertoli cells possess which receptors? Which process do they control?
Spermiogenesis, third phase of spermatogenesis
FSH receptors
Sertoli cells are the primary targets of which 2 hormones?
Testosterone
Androgens
The jcnl complexes b/w Sertoli cells create a barrier…what is the significance of this?
Blood-Testis Barrier
Adluminal & Basal compartments established
What are the functions of the blood-testis barrier?
protects against the autoimmune response
protects against drugs, toxic chemicals
What is the effect of FSH stimulating Sertoli cells?
It releases ABP & this concentrates the testosterone in the seminiferous tubules.
What are the things that are released from Sertoli cells?
Inhibin ABP Anti-Mullerian hormone Testicular Fluid testicular Transferrin Plasminogen Activator
Are Sertoli cells involved in phagocytosis?
yes, it phagocytizes excess material from spermatogenesis.
Anti-mullerian hormone gets rid of paramesonephric ducts. What does this prevent?
regression of female uterine tubes, uterus, upper vagina
The early sperm found in the basal compartment have how many chromosomes?
46 chromosomes
The early sperm found in the adluminal compartment have how many chromosomes?
23 chromosomes
What is the difference in the actions of Leydig cells for fetus, neonate, & teenager?
Fetus: testosterone secreted during the fetal period is responsible for the sexual differentiation of the male
neonate: At birth there are no Leydig cells.
Teenager: as soon as you get to puberty–>LH stimulation of Leydig/interstitial cells causes testosterone secretion–>secondary sexual characteristics.
What are the crystallized proteins found in Leydig cells? What does prolactin do to interstitial cells?
Crystals of Reinke
Prolactin–>steroidogenesis of interstitial cells…
What does testosterone do?
causes spermiogenesis causes male differentiation in utero influences metabolism affects libido develops accessory glands development of secondary sexual characteristics.