back  

Diagram to illustrate spermatogenesis in the human

  
Diagram to illustrate spermatogenesis in the human and those steps which appear to be particularly heat-sensitive. It is largely unclear how a small increase in temperature induces apoptosis. In the adult, both germ cells and Sertoli cells appear to be responsive to heat and show changes in the expression of, for example, heat shock proteins .
embryo gonocytes
Heat sensitive
Adark spermatogonia (stem cells)
postnatal/prepubertal mitosis Apale spermatogonia
puberty meiosis I primary spermatocytes
Heat sensitive
meiosis II secondary spermatocytes
round spermatids
adult mitosis elongating spermatids / spermatozoa
back

Reference:

Source: Lifestyle impact and the biology of the human scrotum.
Reference: Reproductive Biology and Endocrinology 2007, 5:15doi:10.1186/1477-7827-5-15
Authors: Richard Ivell
Licence: Creative Commons Attribution 2.0

© oktober 2007 marius loots