Earthworms have tiny stiff hairs (setae) on almost every segment, and these little hairs help the earthworm move.  As earthworms stretch out and then contract their muscles the setae grab the soil and move the earthworm forward.

The setae are visible under a microscope and their position on the body is used for identification.  On larger earthworms the setae are so large that it makes the earthworm feel rough and bristly.  If you get some big earthworms, be sure to have students feel the setae.

43 Comments

    • SN1 and SN2 are the type of nucleophilic substitution reaction .

      SN1 stands for nucleophilic substitution unimolecular,i.e.when rexn rate depends only upon substrate concn but not upon nucleophile concn.

      whereas in SN2 rate of rexn depends upon concn of both substrate and nucleophile.

  1. I am student of class 11 and I want to be preprad from now for mbbs but I lose my hope sometime and distract although I know u have to learn.

    • The bone present in the middle of skull so called “Sphenoid bone” because it consists of a body, paired greater wings and lesser wings.

  2. Movement of earthworm towards soil surface?
    a)positive geotaxis
    b)negative geotaxis
    c)positive phototaxis
    d)negative phototaxis

Leave a Reply

Your email address will not be published. Required fields are marked *

Post comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.