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Contraction of protoplasm. III. Cinematographic analysis of the contraction of some heterotrichs

✍ Scribed by Alick R. Jones; Theodore L. Jahn; James R. Fonseca

Publisher
John Wiley and Sons
Year
1970
Tongue
English
Weight
550 KB
Volume
75
Category
Article
ISSN
0021-9541

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✦ Synopsis

Abstract

The contraction of Stentor and Blepharisma, in response to mechanical and electrical stimulation and of Spirostomum in response to mechanical stimulation is described. All three species respond to electrical stimulation by contraction of the cytoplasm, beginning at the anodal end regardless of orientation of the animal. The differences in contractile ability and shapes during contraction are discussed in relation to body form and microanatomy. Stentor and Spirostomum also respond to mechanical stimulation. Dropping a weight on the slide causes contraction of the whole body of Spirostomum, but not of Stentor. Stimulation of the oral region of Stentor by means of a vibrating needle causes a contraction of the entire body, but this sensitivity is limited to the oral region. Blepharisma does not respond to mechanical stimulation. Spirostomum and Stentor undergo rapid spontaneous contractions, but Blepharisma does not contract spontaneously.

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