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

Where is the defect in the argyll robertson pupil, Where is the defect in t...

Where is the defect in the Argyll Robertson pupil The defect in Argyll Robertson pupil is due to light near dissociation because pupil react better to near than light.

What is the difference between dna and rna, Concerning their biological fun...

Concerning their biological function what is the difference between DNA and RNA? DNA is the source of information for RNA production (transcription) and therefore for protein s

Can you explain about thoracic aortography, Q. Can you explain about thorac...

Q. Can you explain about thoracic Aortography? Aortic arch angiography has been used to assess aortic valve or aortic root disease. Thoracic aortography is helpful for assessm

Future challenges of management of renewable resources, Define Future chall...

Define Future challenges of management of renewable resources?   In response to past shortcomings in a few fisheries management, and to dealing with other conservation goals

Agreed-upon procedures - non-assurance engagements, Agreed-upon Procedures ...

Agreed-upon Procedures - Non-assurance Engagements Within an engagement to present agreed-upon procedures, the auditor is engaged to carry out those procedures of an audit nat

Define growth and development of infants and preschoolers, Define Growth an...

Define Growth and Development of Infants and Preschoolers? In this unit, we learnt about the various aspects related to the growth and development of infants and preschoolers.

Risk during crown removal-endodontics principles, Risk during crown removal...

Risk during crown removal -Tooth inadvertently extracted using a crown\bridge remover . -Endodontic therapy was performed , and the tooth was replanted , a procedure known

Similaritie and difference between lamarckism and darwinism, What are the f...

What are the fundamental similarities and differences between lamarckism and darwinism? Both darwinism and lamarckism are evolutionary theories as opposed to fixism, both admit

Mechanisms of sex determination and dosage compensation, XYY humans are fer...

XYY humans are fertile males. XXX humans are fertile females. What do these observations reveal about the mechanisms of sex determination and dosage compensation?

#zoology, #what is naturalistic theory?

#what is naturalistic theory?

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