Echinoderm Development. Part 1: Fertilisation and Cleavage

Synopsis: Fertilization and cleavage are shown in the egg of the sand dollar, ‘Dendraster excentricus’. The sperm swim to the surface of the newly spawned eggs through the surrounding layer of the transparent jelly. Within a few seconds of mixing, a sperm fuses with the egg. The fertilization membrane forms. The fertilization cone is formed at the point of fusion with the sperm. The organelles and pronucleus of the sperm move rapidly inward. The two pronuclei fuse forming a zygote nucleus. Cleavage begins after about one hour. The first four divisions produce the blastomeres, and the macromeres and micromeres. A blastocoel begins to form after the fifth. Finally, the fertilization membrane breaks down. The entire process viewed takes about thirteen hours.
Series: Developmental Biology Film Program, Series
Language: English
Country: United States
Medium: Film; Film. 16mm. st. col. 5 min.
Technical information: Black-and-white / Sound
Year of production: 1972
Availability: Hire
Documentation: Notes supplied.
Uses: Developmental courses in biology and zoology.*
Subjects: Biology
Keywords: developmental biology; echinoderms; embryonal development; fertilisation; marine animals; sand dollars; zygotes

Name: Higher Education Film & Video Library
Email: services@bufvc.ac.uk
Web: http://bufvc.ac. External site opens in new window
Phone: 020 7393 1503
Fax: 020 7393 1555
Address: c/o British Universities Film & Video Council
77 Wells Street
London
W1T 3QJ
Notes: Catalogue available from British Universities Film & Video Council.

This record has been viewed 397 times.

British Universities Film & Video Council