Expression of variability, Biology

Assignment Help:

In the preceding section we emphasised the fact that cvolution or the continuous adaptations to the environment can take place only when pheiiotypes exhibit variability. In the absense of variability, the chances arc that existing living organisms would become extinct since with the change in the environment these organisms would die without leaving progeny. Fortunatcly in living systems mutations and recombinations generate the required variability. However, organisms often strive to arrive at populations which are more or less uniform. This is possible because selection process acts in such a way that a certain degree of uniformity of phenotype is imposed among individuals of n population. If an individual were to be vcry different in some way from thc rest of the population. he would be less well adapted to the environment as compared to other members of the population and therefore unable to compete successfully with them. However, in a continuously changing environment, a slight phenotypic variability should be maintained in a population. In a changing environment no phenotype remains optimally adapted for long. This is the precise reason why variability needs to be generated continuously in a population and used to develop adaptations in the way Darwin suggested. We shall look into the mechanisms that generate variability.


Related Discussions:- Expression of variability

Explain about the niacin (nicotinic acid) deficiency, Explain about the Nia...

Explain about the Niacin (nicotinic acid) deficiency? Niacin (nicotinic acid) deficiency classically results in pellagva, which is a chronic wasting disease associated with a c

Methods by which diseases are transmitted, There are several methods by whi...

There are several methods by which a disease-causing organism can be transferred from the reservoir to the host organism. Direct contact : Disease - causing organism may be tr

Describe the use of sorbates acid in microorganisms, Q. Describe the use of...

Q. Describe the use of Sorbates acid in Microorganisms? Sorbic acid is an unsaturated carboxylic acid whose salts as sodium, calcium or potassium are used in foods upto

How can denaturation be classified, Q. How can denaturation be classified c...

Q. How can denaturation be classified concerning its reversibility? Protein denaturation can be an irreversible or a reversible process, i.e., it may be impossible or possible

Explain about bioactive materials, Explain about Bioactive materials Bi...

Explain about Bioactive materials Bioactive materials: Certain glasses, ceramics, and glass-ceramics that contain oxides of silicon, sodium, calcium and phosphorus (SiO 2 , Na

How dna molecules are formed, As a result of DNA replication two DNA molecu...

As a result of DNA replication two DNA molecules come into existence. Why is it not correct to assert that two "new" DNA molecules are created? What is the name given to the proces

Study giude, how many atoms are H2SO4 compound

how many atoms are H2SO4 compound

How physical activity affect requirement of protein, How Physical Activity ...

How Physical Activity affect requirement of protein? Research on protein needs for muscular work had its beginning in 1863 when Von Leiberg postulated that muscle protein was d

Define the reduction of the activation energy, How does the formation of th...

How does the formation of the enzyme-substrate complex define the reduction of the activation energy of chemical reactions? The enzyme possibly works as a test tube within whic

#titlemicrobiology.., topics relating research on microorganisms and their ...

topics relating research on microorganisms and their application ?

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