PTC gene has two main alleles; one that codes for tasting and the other non-tasting. The allele for tasting determines a trait of tongue papillae that can bind the PTC molecules. Non-tasting allele forms papillae that are unable to bind PTC effectively. Therefore, the combination of these alleles in the genotype of a person determines their phenotype – PTC sensitivity.

2b2t

explanation:

2b2t

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.