Theory of embryology - pre-formation theory, Biology

PRE FORMATION THEORY -

  1. Proposed by Marcello Malpighi.
  2. Studied chick egg and proposed his work in "De ova-incubato".
  3. According this different part of embryo previously present in the eggs. These parts developed through the growth.
  4. Swammerdam proposed that the sex cell contain preformed emrbyo or a more or a less perfect miniature of the adult.
  5. Ovists view - This theory was supported by Malpighi, Spallanzani, Haller, Bonnet and swammerdam. These scientists belived that miniature organism was present in the eggs were called ovist.
  6. Spermist view - Leeuwenhoek and Hartsoeker believed that miniature of organism was present in the head of sperm. This miniature is called hommunculus in man and animalcule in other animals.

1978_miniature of sperm.png

Miniature in Mammalian Sperm

Posted Date: 10/3/2012 6:47:58 AM | Location : United States







Related Discussions:- Theory of embryology - pre-formation theory, Assignment Help, Ask Question on Theory of embryology - pre-formation theory, Get Answer, Expert's Help, Theory of embryology - pre-formation theory Discussions

Write discussion on Theory of embryology - pre-formation theory
Your posts are moderated
Related Questions
Purpose of Supervision: Purpose: To help the personnel to grow, to know themselves and what they need in order to render the most efficient service and to give them assistance

outline the process of yeast fermentation stating all enzymes involved

Q. What is Counsellor? Counsellor is someone who gives advice about the problem. A counselor's role is to help patients help themselves. In our context  a counsellor is  a comm

Explain Gene Expression - Nutrient Gene Interactions? The last two decades have witnessed tremendous development in our understanding of the cellular processes at the molecular

Arterial Blood Gas Studies: Purpose 1)  A measurement of partial pressure of oxygen and carbon dioxide  in arterial blood, as well as the pH  of  the blood.  2) The Partial p

Q What do protozoans "eat"? Do they move in search for food? Protozoans are heterotroph beings that are they do not make their own food and thus they need to search for it in t

In certain instances differences in the morphology of genitalia between species make it impossible for normal mating to occur, and sympatric species tend to remain isolated. When t

how can i calculate the energy released from burnt peanut

Biogeochemical Cycling - Nutrient Cycles The energy flows through ecosystems enabling the organisms to perform various kinds of work, and is ultimately lost as heat. It is gon

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