Interesting Q & A session by one of the curious student
Jaivikshastram is an open forum for posting questions and Team Jaivikshastram get back to you soon. This is one of the first Q & A we got.
Yogesh :
How recesive traits are masked by dominant traits ?
Before answering the question we should know difference between dominant and recessive allele.
eg. For height T and t where T is responsible for synthesis of Gibberellic acid.
The dominant or recessive decided is at organism level. But at molecular level all alleles are co-dominantly expressed.
For ex. In sickle cell anemia if both alleles expressed are sickle that is nonfunctional alleles then produce sickle shape red blood cell (RBC) and if heterozygous then the produce intermediate shape RBC to that of the normal.
At individual level the person may have sickle anemia of carrier for the disease but at molecular level it have both nonfunctional or semi functional alleles.
We can also take an example of T and t in accordance with the plant but in plant development environment plays a crucial role.
As recessive is non-functional then there is nothing like masking as such.
Thanks for being curious Yogesh, Keep asking Questions, be curious.
Yogesh :
Firstly i would like to thank you. you cleared me that, both genes are expressed at molecular level, but what about pea plant height in F1 heterozygous condition ?
Height is the phenotype based on plant hormone Gibberellic acid. In F1 we get all tall plants because expression of t is much more less than T that we cannot observed it in phenotype. In F1 all pea plants become tall whether the genotype is TT/ Tt .