Codominance, Biology

Assignment Help:

CODOMINANCE

The alleles which do not show dominance-recessive relationship and are able to express themselves independently when present together are called codominant alleles. Independent expression of two alleles in an individual is termed codominance.

Example :- 1

Coat colour in short horned cattle

There are two types of pure short horned cattle, red and white. On cross breeding the individuals of F1 generation are found to have roan colour. The effect is produced due to juxtaposition of small patches of red and white colour. It is also known as mosaic inheritance. As both the alleles form small patches side by side, they are codominant. It was previously considered to be a case of incomplete dominance because the colour effect is intermediate between red and white, on in breeding the roan hybrids produce three type of cattle-red, roan and white in the ratio of 1 : 2 : 1.

Example :- 2

AB Blood Group

Alleles for blood group A (IA) and blood group B (IB) are codominant so that when they come together in an individual they produce blood group AB. It is characterised by the presence of both antigen A (from IA) and antigen B (from IB) over the surface of erythrocytes.

Example :- 3

MN Blood Group

This phenomenon has been observed in MN blood group in humans. The red blood cells can carry two types of native antigens M and N, and an individual can be MM, MN or NN, exhibiting either one or both of them.

Example :- 4

Sickle Cell Haemoglobin

The allele for sickle cell haemoglobin Hbs is codominant with allele for normal haemoglobin HbA.


Related Discussions:- Codominance

How to antioxidants work in cancer prevention, How to antioxidants work in ...

How to antioxidants work in Cancer Prevention? As cells function normally in the body, they produce damaged molecules called free radicals. These force radicals, we learnt are

What is the development of benthics, Dr. Don McPhail and his colleagues hyp...

Dr. Don McPhail and his colleagues hypothesized that the existence of the benthic and limnetic sticklebacks is the result of allopatric speciation. Although this may be true for so

Dictyosomes, Dictyosomes  are produced on the Organelles in the plant cells...

Dictyosomes  are produced on the Organelles in the plant cells composed of the series of flattened membrane sacs which sort, chemically modify, and package protein srough endoplasm

Limitations of doppler echocardiograph, Though  it has bees suggested that ...

Though  it has bees suggested that Doppler echocardiography may be useful for non-invasive determinations of  stroke volume and cardiac output, it  should be recognized that th4re

Protoplasmic streaming and tubular peristaltic flow model, Protoplasmic Str...

Protoplasmic Streaming and Tubular Peristaltic Flow Model The first of the above two models involves the well known phenomenon of cytoplasmic streaming in giant algal cells. C

What are the degenerative diseases of the nervous system, Q. What are the m...

Q. What are the main degenerative diseases of the nervous system? The major degenerative diseases of the nervous system are Alzheimer's disease and Parkinson's disease. The

Terminology use in apical dominance, Terminology use in Apical Dominance ...

Terminology use in Apical Dominance Here are a few terms that will be used in discussing apical dominance. A clear understanding of these terms is needed for understanding the

Excretion, what is the excretory organ of agama lizard

what is the excretory organ of agama lizard

Show endocrine glands involved in the menstrual cycle, Q. What are the endo...

Q. What are the endocrine glands involved in the menstrual cycle? What are the hormones in action? The endocrine glands that secrete hormones involved in the menstrual cycle ar

Budding- asexual reproduction, Normal 0 false false false ...

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

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