Mechanisms of flagellar motility deduced from backward-swimming bull sperm
✍ Scribed by Phillips, David M. ;Kalay, Dan
- Publisher
- John Wiley and Sons
- Year
- 1984
- Tongue
- English
- Weight
- 741 KB
- Volume
- 231
- Category
- Article
- ISSN
- 0022-104X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Under certain conditions of cryopreservation, bull spermatozoa undergo an interesting structural alteration. The sperm tail becomes bent back on itself to form a hairpin shape. The bend in the tail occurs at a very precise point, 11 μm behind the neck, and it causes the tail to become kinked. Flagellar microtubules and dense fibers become broken and the ninefold symmetry of the flagellum is greatly distored. Although the portion of the flagellum between the kink and the sperm head does not propagate a wave, the distal portion of the flagellum propagates a base‐to‐tip wave, causing the spermatozoan to progress backward. These observations suggest that the mammalian spermatozoon does not need basal structures to propagate a flagellar wave.