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Updated: May 3, 2026
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Cytological Analysis of Spermatogenesis: Live and Fixed Preparations of Drosophila Testes
Published on: January 20, 2014
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Spermatogenesis in Polytrichum juniperinum : II. The mature sperm
D J Paolillo1, G L Kreitner, J A Reighard
1Department of Botany, University of Illinois, Urbana.
Planta
|February 14, 2014
Summary
Mature Polytrichum sperm feature condensed chromatin nuclei and distinct basal bodies. Microtubules form a filamentous appendage, with the cytoplasmic remnant containing plastids and mitochondria.
Area of Science:
- Plant biology
- Sperm cell development
- Bryophyte reproductive biology
Background:
- The mature sperm of Polytrichum, a bryophyte, undergoes significant structural reorganization.
- Understanding sperm morphology is crucial for comprehending plant reproduction.
Purpose of the Study:
- To detail the ultrastructural organization of mature Polytrichum sperm.
- To identify key components and their fates during sperm development.
Main Methods:
- Transmission electron microscopy was used to examine the ultrastructure of mature Polytrichum sperm.
- Detailed morphological analysis of nuclear, basal body, microtubule, and cytoplasmic components was performed.
Main Results:
- Mature sperm nuclei exclusively contain condensed chromatin.
- The apical basal body is elongated, while the anterior basal body remains short.
- Persistent microtubules from the multilayered structure form the sperm's filamentous appendage.
- The cytoplasmic remnant retains plastids and mitochondria not involved in apical body formation.
Conclusions:
- Polytrichum sperm exhibit a highly specialized structure adapted for motility and fertilization.
- The differentiation process involves precise organization of cytoskeletal and organellar components.
- This study provides detailed insights into the ultrastructure of bryophyte sperm.
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