Question #85c5f

1 Answer
Jul 18, 2015

They differ in their alleles.

Explanation:

If in a diploid organism, both the alleles are the same, the organism is said to be Homozygous .

For example, let us consider the example of the Pea plant. It has 2 alleles for its seed shape- Round and Wrinkled. Out of these 2, round is dominant over wrinkled. The dominant character is written in capital letter and the recessive in small. In this case, round would be R and wrinkled would be r.

If in a diploid organism, both the alleles are different, the organism is said to be Heterozygous.

Pure round- RR
Pure wrinkled- rr

Both RR and rr are homozygous as the same allele R is repeated twice.

If we consider a hybrid round plant, the case will be different. (Hybrid is heterozygous- with 2 different alleles).

Hybrid round- Rr
Here, both alleles R and r are present. So it is heterozygous .

*Remember that heterozygous is only when both alleles are present. When a plant is heterozygous it will express the dominant character even though it has the recessive gene in it.

Hope this helps! :)