what are dominant and recessive traits ? give one example
Answers
Answer:
=> Alleles are described as either dominant or recessive depending on their associated traits.
Since human cells carry two copies of each chromosome? they have two versions of each gene?. These different versions of a gene are called alleles?.
Alleles can be either dominant? or recessive?.
Dominant alleles show their effect even if the individual only has one copy of the allele (also known as being heterozygous?). For example, the allele for brown eyes is dominant, therefore you only need one copy of the 'brown eye' allele to have brown eyes (although, with two copies you will still have brown eyes).
If both alleles are dominant, it is called codominance?. The resulting characteristic is due to both alleles being expressed equally. An example of this is the blood group AB which is the result of codominance of the A and B dominant alleles.
Recessive alleles only show their effect if the individual has two copies of the allele (also known as being homozygous?). For example, the allele for blue eyes is recessive, therefore to have blue eyes you need to have two copies of the 'blue eye' allele.
Answer:
Every gene has two or more alleles or in simple words we can say that every trait has different characteristics. For ex. if colour is a gene then green and yellow will be alleles.
Now out of the two alleles one is dominant over the other and can be expressed in heterozygous condition also. For ex. in pea plant that is pisum sativum the allele for height which is dominant is tall height and it can be expressed as Tt or TT.
Whereas the dwarf height is a recessive trait amd can only be expressed in homozygous condition tt and not im heterozygous condition Tt.
Hope it helps..
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