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 apoptosis, Changes those are associated with programmed cell death,...

Changes those are associated with programmed cell death, containing release of apoptotic bodies, blebbing, and nuclear fragmentation.

State the objectives of neuropsychological assessment, State the goals of N...

State the goals of Neuropsychological assessment Neuropsychological assessment therefore has twin goals. i) The first goal is to recognize the disrupted psychological compo

Coadapted communities, From your studies in ecology, you must be aware that...

From your studies in ecology, you must be aware that most ecosystems are quite complex consisting of several habitats and that habitats in turn are composed of microhabitats. Each

Subphylum opalinata, Subphylum Opalinata Body covered with longitudin...

Subphylum Opalinata Body covered with longitudinal rows of cilium like ,organelles but true ciliature absent. Parasitic; cytosome lacking; two to many nuclei of one type.

What is septa, What is Septa Septa are thin bony plates, which divide t...

What is Septa Septa are thin bony plates, which divide the inferior portion of the antrum into sections and may even create separate compartments. A buttress or web formation m

Influence of yolk on cleavage, Influence of Yolk on Cleavage Though b...

Influence of Yolk on Cleavage Though biological significance of yolk is to provide nourishment to the developing embryo, it is not part of the active cytoplasm. Yolk is dead

What are the identical proteins, Q. Are proteins with the same number of ea...

Q. Are proteins with the same number of each dissimilar amino acid that forms them necessarily identical proteins? Even if many proteins have the same number of each different

Major divisions of the chordate phylum, Q. What are the two major divisions...

Q. What are the two major divisions of the chordate phylum? Chordates are divided into vertebrates and protochordates (urochordates and cephalochordates). Q. What are the d

Right coronary artery, Right coronary artery arises from the anterior aorti...

Right coronary artery arises from the anterior aortic sinus. It runs down along the anterior part of the coronary sulcus, reaches the lower border of heart turns round the lower bo

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