B. White petal colour is a recessive trait.
Explanation:
In Mendelian genetics, the alleles depicted in small letters are recessive traits.
Since both alleles are same and in lower case they are homozygous recessive alleles for a white coloured petal gene.
The genotype of the trait will be tt because if it is crossed either with heterozygous or homozygous P alleles it will appear as tt to have phenotypic trait of white colour.
So the genotype will be tt.
The answer to this is Carbon Dioxide.
They say how an enzyme perfectly fits into its substrate is alike a "lock and key".
Only one specific enzyme can fit a specific substrate.
The amount of DNA present in the system of an organism that does not necessarily relate to how complex that certain organism is. There are single-celled microorganism with very few amount of DNA but are very complex with respect to arrangement of certain amino acid component of the DNA strands.