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

Describe what are non degradable pollutants, Question : (a) Briefly de...

Question : (a) Briefly describe what are non degradable pollutants? (b) What do you meant by ichthyosarcotoxic fishes and give two examples of ichthyosarcotoxic fish poiso

Mechanism of enzyme action, Mechanism  of Enzyme Action  The action of...

Mechanism  of Enzyme Action  The action of enzymes is to lower  the activation energy  or threshold  of their substrates which. Therefore  become  activated and   react  with

Briefly explain about archenteron and blastopore, Q. What are the archenter...

Q. What are the archenteron and the blastopore? What is the stage of the embryonic development in which these structures are formed? What are the destinations of the archenteron an

Show the directly visible chemical characters, Q. Show the Directly Visible...

Q. Show the Directly Visible Chemical Characters? Very few chemical substances in plants can be observed directly, but the few substances such, starch grains which are pres

Analyze the chromosomes of her daughters or of her sons, Is it more indicat...

Is it more indicated for a geneticist desiring to map the X chromosome of the mother of a given family (the researcher does not have access to her DNA, only access to the genetic m

Implantation - pre-embryonic development, Implantation - Pre-Embryonic Deve...

Implantation - Pre-Embryonic Development After entering the uterus and formation of ICM, the blastocyst starts to embed in the endometrium of the uterine wall. By one week aft

What is osmotic diarrhoea, Q. What is Osmotic diarrhoea? This kind of d...

Q. What is Osmotic diarrhoea? This kind of diarrhoea is caused by the presence of osmotically active substances in the intestinal tract, which in turn, favour the drawing of la

Solutions of hydrocarbons evaporate at room temperature, The fact that some...

The fact that some pure solutions of hydrocarbons do not readily evaporate at room temperature is a result of Select one: a. London dispersion forces. b. The hydrophobic effe

Structures of a flowering plant, Which structures of a flowering plant give...

Which structures of a flowering plant give rise to (a) potatoes, (b) the fleshy scales of an onion?   (a) A potato is a tuber formed at the end of an underground stem (b) O

Erythema - common disorders of skin, Erythema: Erythema is one of  the...

Erythema: Erythema is one of  the,commonest primary lesions of  the skin. It  is produced by  the dilation of the cutaneous blood vessels.  If the dilation  is accompanied  by

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