Abstract:
:High speed cinemicrographs were made of sea urchin sperm at temperatures varying from 22 to 6 degrees C. Apparatus, combining a television camera and a video digitizer, was constructed to scan individual flagellar images and to digitize the flagellar waveforms. With appropriate smoothing and averaging procedures, the rough data were condensed by a microcomputer into the coordinates of 20 points along a flagellum, spaced 2 microns apart. The curvature of the flagellum at these points was also computed. The coordinates of the flagellar positions were obtained to an accuracy of approximately +/- 0.1 micron, flagellar curvature to an accuracy of approximately +/- 50 cm-1. At all temperatures the amplitude of the flagella was found to vary with time in a purely sinusoidal fashion to within +/- 2%. The local curvature of the flagella had basically a purely sinusoidal time course to within +/- 50 cm-1, but a varying amount of asymmetry was present in the distal and the proximal ends of the flagella. This asymmetry in the curvature was related to the radius of the circular path of the sperm. The flagellar waveforms can probably be summarized in simple algebraic functions.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Rikmenspoel R,Isles CAdoi
10.1016/S0006-3495(85)83931-Xsubject
Has Abstractpub_date
1985-03-01 00:00:00pages
395-410issue
3eissn
0006-3495issn
1542-0086pii
S0006-3495(85)83931-Xjournal_volume
47pub_type
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