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

What is eutrophication in ecology explain briefly, What is Eutrophication i...

What is Eutrophication in ecology explain briefly? Freshwater ecosystems demonstrate the close relationship between aquatic and terrestrial ecosystems. Until recently, most peo

Experiment, I need an idea for a Biology experiment

I need an idea for a Biology experiment

Enumerate the failures in adaptation, Enumerate the Failures in adaptation ...

Enumerate the Failures in adaptation Failures in adaptation, such as poor school performance or unsatisfactory peer relationships are usually problems that bring children to th

How cleaning agents works, Q. How Cleaning agents works? Food particles...

Q. How Cleaning agents works? Food particles and other debris provide good nutrients for the nlicroorganisms to grow. In fact, the food particles protect microorganisms d

Alcohol related emergencies, Alcohol Related Emergencies: Alcohol is o...

Alcohol Related Emergencies: Alcohol is one of  the most serious health problems. Alcoholism is defined as a primary or chronic disease with genetic, psychological and environ

Comparison to healthy lungs, The nature of the sounds produced by percussio...

The nature of the sounds produced by percussion (tapping) a patient's chest can tell a physician a great deal about the condition of the organs within the thoracic cavity. Healthy,

How much time is required for a single cell, How much time is required for ...

How much time is required for a single cell of Detoxivicatium completeium to grown into a population large enough to fill the volume of the earth?

Parthenocarpy, Parthenocarpy It is generally observed that the fruit d...

Parthenocarpy It is generally observed that the fruit develops after fertilization and it has fertile seeds inside it. However, this is not always so. Fruits of certain variet

What is the main theory opposed to evolution, What is the main theory oppos...

What is the main theory opposed to evolution? The major theory that opposes the evolution theory on the description of how species emerged (phylogenesis) is fixism.

Natural selection under different environments condition, In the absence of...

In the absence of any large scale envirorrmental change that is, in more or less uniform environments, populations often maintain a stable genetic constitution with respect to many

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