questions 0

Spermatogenesis

Author:
Topic updated on 05/13/17 12:13pm

Overview
 

 
Introduction
  • A process by which spermatogonia develop into spermatozoa
    • begins at puberty
    • requires 64 days (approximately 2 months)
  • Broken down into
    • spermatogenesis
      • the formation of spermatids from spermatogenic cells
    • spermiogenesis
      • the process of spermatids maturing into mature sperm
Spermatogenesis
  • Spermatogenic cells are organized in poorly defined layers of progressive development between adjacent Sertoli cells in seminiferous tubules
  • Spermatogonia (2N), most immature spermatogenic cells, rest on basal lamina
    • spermatogonia occupy basal compartment in seminiferous tubules
  • Spermatogonia (2N) divide by mitosis
    • produces primary spermatocytes (2N)
  • Primary spermatocytes (2N) replicate DNA (4N)
    • primary spermatocytes move across Sertoli cell - Sertoli cell junctional complexes into luminal compartment in seminiferous tubules
  • Primary spermatocytes (4N) divide by meiosis I
    • produces 2 haploid secondary spermatocytes (2N)
  • Secondary spermatocytes (2N) divide by meiosis II
    • produces 4 haploid spermatids (1N)
Spermiogenesis
  • Spermatids (1N) differentiate into spermatozoa (1N) by an extensive remodeling process
  • Loss of cytoplasm, gain of acrosomal cap, and flagellum (tail)
    • acrosomal cap develops via Golgi apparatus
    • flagellum (tail) develops via centrioles
Spermatozoa
  • Head
    • acrosomal cap and nucleus
  • Tail
    • neck
    • middle piece
      • mitochondria provide energy for movement of flagellum (tail)
        • sperm motility
    • principal piece
    • end piece
  • Nutrition
    • spermatozoa feed on fructose


  RATE CONTENT
3.0
AVERAGE 3.0 of 5 RATINGS

Qbank (0 Questions)


Recent Videos

video
This video describes spermatogenesis. NOTE: All Khan Academy content is availabl...
2/22/2015
174 views
5

Evidence & References Show References




Topic Comments

Subscribe status: