Gametogenesis, Biology

The process by which gametes are produced in the gonads is known as gametogenesis.

The process of formation of male gametes or sperm is known as spermatogenesis is of great significance be- cause the gamates are the only link between the generations.

Their nuclear DNA is the depository of all those genetic informations that are needed in the development of new organism.

In monoecious or hermaphroditic animals both male and female gametes are produced in the same individual.

In dioecious animal, the sperm and ova are formed in different individual, but in same species.

ORIGIN OF PGC IN INVERTEBRATE ANIMAL

In invertebrate animal PGC originate in embryonic development. e.g. Ascaris & drosophila.

ORIGIN OF PGC IN VERTEBRATE ANIMAL

In vertebrate animal PGC originated due to separation of germ plasm through somatic plasm.

PGC determined in vertebrates as follows -

1.       In fishes - PGC originate by endoderm and establish in developing gonads.

2.       In amphibians - Specific cytoplasm present in vegital pole of egg. This cytoplasm form the PGC.

3.       In reptiles and aves - PGC originated outside the gonads. eg. in chick embryo PGC originate posterior part of disc and the migrate toward the anterior part and carry through blood circulation in the developing gonads.

4.       In mammals - The PGC are formed near the yolk sac from the endoderm (Gonads formed from mesoderm)

Posted Date: 10/3/2012 7:20:08 AM | Location : United States







Related Discussions:- Gametogenesis, Assignment Help, Ask Question on Gametogenesis, Get Answer, Expert's Help, Gametogenesis Discussions

Write discussion on Gametogenesis
Your posts are moderated
Related Questions
Q. What is the group of the phylum Chordata that first colonized the terrestrial environment? From which habitat did they come? Partially aquatic partially terrestrial animals,

Explain the Interaction of Vitamin A with Vitamin E? Of the various nutrients, the interaction of vitamin E, proteins, zinc and iron with vitamin A is of significance. Know? Le

what is detergent pollution and it''s effects and causes

Explain diet from Lifestyle Risk Factors ? The lifestyle factors are the way of living of an individual and comprise of the diet, smoking, alcohol, physical activity and stress

#affinities of ctenophora with platyhelmintheson..

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Q. What is pericardial effusion? A pericardial effusion is viewed as an echo free space surrounding the heart, most commonly seen posteriorly. Echocardiography provides

why is epidermis peeledsuggest why a marine amoeba does not have a contractile vacuole

Some organisms contain enzymes that condense a fatty alcohol and a fatty acid to generate wax esters. Draw decanol, plamitic acid (C16:0 fatty acid) and the resulting wax ester gen

OTHE R GLANDS - (i) Mammary glands - Study of mammary gland is mastology. Modified sweat gland. 4-5 pairs in rabbit. 1 pair in human. In opposum 25 pairs (max.).