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

Explain the loss of carotenoids, Explain the loss of carotenoids In pro...

Explain the loss of carotenoids In processing fruits and vegetables, loss of carotenoids into cooking or canning water is very slight. However, carotenoids undergo oxidation wh

Define advantages of membrane filtration technique, Define Advantages of me...

Define Advantages of membrane filtration technique? (i) Both total and viable counts can be obtained. (ii) Specific microorganisms can be selected by using special media.

Explain the dietary fibre and colon cancer, Explain the Dietary fibre and c...

Explain the Dietary fibre and colon cancer? The relationship between colorectal cancer and dietary fibre remains complex. Although a cause-and-effect relationship between fibre

Monkeey Opsin Evolution, Why does having three color receptors (a.k.a. opsi...

Why does having three color receptors (a.k.a. opsins) lead to a more complex color perception than just two?

Muscle cells, explain why it is essential that muscle cells, during anaerob...

explain why it is essential that muscle cells, during anaerobic respiration, convert pyruvic acid(pyruvate) into lactic acid, even though the conversion results in an accumulation

Valvular heart diseases and its causes, Valvular Heart Diseases Normal...

Valvular Heart Diseases Normal heart valves function to maintain a uni-directional flow of blood through cardiac chambers. Two basic problems that compromise the normal functi

Explain the principle or theory of biuret method, Explain the Principle or ...

Explain the Principle or Theory of biuret method? If a strongly alkaline solution of Biuret is heated with very dilute copper sulphate, a violet colour is obtained. The substan

Explain what is genetic engineering, Explain brifly what is Genetic Enginee...

Explain brifly what is Genetic Engineering ? Genetic Engineering : Engineering techniques have been used in agriculture and horticulture for centuries. Certain plants or ani

What are the corals, Q What are the corals? Corals are characterized by...

Q What are the corals? Corals are characterized by their polypoid shape, slow growth and sessility and secretion of a solid skeleton made of calcium carbonate. Numerous coral i

Point out some difference between tumor and cancer, Point out some Differen...

Point out some Difference between Tumor And Cancer? Tumor is a swelling or growth because of an abnormal growth of tissue. Tumors can either be benign or malignant. The benign

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