Cell determination, Biology

Cell Determination

Cell determination is a process through which portions of embryonic genome are selected for expression in particular embryonic cells. Determination to follow a specific pathway of differentiation precedes the appearance of any type of visible change in biochemistry or morphology of the cell. We know of two major ways through which determination takes place. in one way certain factors that reside in the cytoplasm of embryonic cells (intrinsic factors) control cell determination. These factors are considered to as ooplasmic or cytoplasmic determinants. During cleavage they are passed on to particular blastomeres whose future differentiation is so finally decided. This process is also called determination by cytoplasmic segregation.

In the other method, the final cell fate is determined through extrinsic factors that originate outside the cells. The extrinsic factors include:

1) The instructions acquired as a function of the position of blastomeres within the embryo,

2) Signals that are transmitted among the blastomeres.

This second process is termed as embryonic induction in which the cell fate is determined by signals received from different cells. In different species determination takes place at different times during development. It may be very early or it may take place at relatively much later stages. In quite a number of animal groups, like annelids, molluscs, tunicates etc. the fates of the blastomeres resultant from the first few cleavage divisions are already determined. Such types of eggs and embryos are called determinate or mosaic. In others such as echinoderms and vertebrates final determination takes place much later, even as late as during or after gastrulation, and they are said to have indeterminate or regulative eggs.

Posted Date: 1/29/2013 12:14:26 AM | Location : United States







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

Write discussion on Cell determination
Your posts are moderated
Related Questions
Explain Serum lipoprotiens Serum lipoprotiens:- spherical  or  ellipsoidal  particles containing  proteins, cholesterol esters  and  triacylglycerols, encased  within  a mon

How will the plant-incorporated protectants rules change EPA's current registration process? The rules clarify which plant-incorporated protectants are needed to be evaluated u

Q. Which organs of the body is part of the human digestive system? The digestive system also known as "systema digestorium" or gastrointestinal system is composed of the digest

Explain the Working Principle of Spectrophotometer? The working principle of spectrophotometer is graphically presented in Figure. Figure: Working princip

Physical Lay Out: Physical lay out of the nursing unit should be planned and built in such a manner so that it helps the head nurse to discharge her duties/carry  out her resp

Q. How the DNA nanoarchitecturing works? DNA Nano architectures constructs that can be self-assembled from branched DNA molecules. Their components can be simple branched speci


Determine the term - coupling factors The coupling factors, also called the F l ATPase, present on the inner mitochondrial membrane facing the matrix side, are a very complex a

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

My friend was injured several years ago in a car accident and she was diagnosed with a herniated disc. Can you please explain using the correct anatomical terminology what herniati