Question

how can we say that a factor is present but not expressed ?
pls answer....

Answer 1

Ciao,
this is because of dominance as in case of a gene it has two alleles .one can be dominant over otger allele and thus we see the character shown by dominant allele but at the same time the ressesive allele has its character but it is not expressed.this means that the presence of ressesive allele is functionally hidden.
eg.
we have R allele with round shape and r with wrinkled. when they two combineallele R is dominant over r so the hetrozygote Rr has round shape
i really hope that you find this answer helpful .
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