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

Deficiency diseases-neonatal hypoglycaemia, Neonatal  hypoglycaemia Hy...

Neonatal  hypoglycaemia Hypoglycaemia is a metabolic condition of newborn piglets that develops in first few days of life due to decreased caloric intake and increased cataboli

Explain surgery process for head and neck tumor, Define Surgery Process for...

Define Surgery Process for Head and Neck Tumor? Treatment mostly involves combination of surgery and radiation. Chemotherapy is also used in some cases, we will learn about the

Explain about human auditory sensitivity, What are the structures that part...

What are the structures that participate in the human auditory sensitivity? The structures of the human auditory sensitivity are the ears (external, middle and internal), the

Do plants have tissue organization and specialized organs, Do plants have t...

Do plants have tissue organization and specialized organs? Plants have specialized organs (as reproductive organs, roots, limbs, leaves) and differentiated tissues (vascular t

What happens to the movement of molecules at equilibrium, What happens to t...

What happens to the movement of molecules at equilibrium? At equilibrium, the movement of molecules continues, but because there is no concentration gradient, there is no net m

Applied Biology, Which of the branches of applied biology ?

Which of the branches of applied biology ?

Explain about the biofertilizers, Explain about the Biofertilizers Biof...

Explain about the Biofertilizers Biofertilizers, are the cultures of microorganisms used for inoculating seed or soil or both under ideal conditions to increase the availabilit

Cephalisation - metazoa, Cephalisation - Metazoa Bilateral animals whe...

Cephalisation - Metazoa Bilateral animals when creeping or swimming, have a tendency to keep the same end of the body forward and the same surface down towards the substratum.

Describe class diplopoda and chilopoda in detail, Describe Class Diplopoda ...

Describe Class Diplopoda and Chilopoda in detail? Members of the Subphylum Crustacea and the Subphylum Uniramia have one major characteristic in common. Both groups have biting

Coa to succinate in the citric acid cycle, Name the high-energy complex gen...

Name the high-energy complex generated during the conversion of succinyl CoA to succinate in the citric acid cycle GTP  or  ATP is  the high-energy  complex generated during th

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