Fertilization in earthworm, Biology

Assignment Help:

In earthworms, when the ovaries mature, the clitellum secretes a viscous substance in the form of a girdle. This girdle hardens in to a cocoon around the clitellum. The ova are discharged into cocoon. When this cocoon moves over the spermathecae openings, the sperms which are already collected from another worm and stored in the spermathecae are discharged into the cocoon. The cocoon finally, comes out of the body and fertilization takes place in the cocoon. As it is taking place outside the body, it is called as "external fertilization".


Related Discussions:- Fertilization in earthworm

Winter stratification - thermal stratification, Winter Stratification - The...

Winter Stratification - Thermal stratification During extremes of winter the surface layer of the lake freezes or attains a temperature close to 0° Celsius. Under these condit

Transcribed regions, Transcribed regions The transcribed regions of the...

Transcribed regions The transcribed regions of the genes contain a number of regulatory elements that control exon splicing, mRNA transfer to cytoplasm translation, mRNA target

Draw a diagram of transverse section of mammalian bone, Draw a diagram of t...

Draw a diagram of transverse section of mammalian bone and label the following parts in it: (i) Haversian canal (ii) Lacuna containing osteocytes (iii) Canaliculi

How gender affects the bmr, How Gender affects the bmr? We have already...

How Gender affects the bmr? We have already emphasized earlier that sex difference in metabolic rates are primarily attributable to difference in body size and composition. Wom

Which disorders is most likely to underlie, A healthy, primiparous (first-t...

A healthy, primiparous (first-time) mother delivered a healthy infant several hours ago, but the mother has experienced postpartum hemorrhage. Which of the following disorders is m

Of which substances is chromatin made, Of which substances is chromatin mad...

Of which substances is chromatin made? Chromatin is made of DNA molecules associated to proteins known as histones. Cell Nucleus Review - Image Diversity: chromatin

Pseudopodia – protozoans, Pseudopodia – Protozoans Pseudopodia are flo...

Pseudopodia – Protozoans Pseudopodia are flowing cytoplasmic protrusions of the cell causing amoeboid movement. In protozoans pseudopodia exist in several forms. The most fami

Name the enzyme included in the continuous replication, Mention the informa...

Mention the information that the health workers get by measuring BOD of a water Body. a) Name the enzyme included in the continuous replication of DNA strand. Mention the Polar

Organs involved in the digestion process, The various organs involved  in...

The various organs involved  in  the digestion process are: Alimentary tract which  includes mouth, pharynx, esophagus stomach, small intestine, large intestine, appendix,  rec

Explain about amino acids, Do the -R groups bound to the central carbons pa...

Do the -R groups bound to the central carbons participate in the union among amino acids? The peptide bond attaches the nitrogen of the amine group of one amino acid to the car

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd