Question

in some traits, different phenotypes result from genes whose alleles each contribute a specific increment to the whole. the phenotypes then have a discontinuous phenotypic distribution. group of answer choices true false

Answer 1

The statement is false; when multiple genes contribute increments to a trait, resulting in a range of phenotypes, this is known as polygenic inheritance, which typically leads to continuous, not discontinuous, phenotypic distribution.

Step-by-step explanation:

The statement that traits with different phenotypes resulting from genes whose alleles contribute specific increments to the whole, leading to discontinuous phenotypic distribution, is false. The scenario described in the question refers to polygenic inheritance, where multiple genes contribute to a phenotype. This type of inheritance typically results in a continuous distribution of phenotypes rather than a discontinuous one. Discontinuous variation is characterized by distinct categories of phenotype, typically arising from a single gene or a small number of genes with major effects. An example of a discontinuous trait is flower color in Mendelian peas, where the flowers are either purple or white, with no intermediates. Conversely, human height is an example of polygenic inheritance, with a range of heights reflecting the contributions of many genes.

On the other hand, discontinuous variation is when traits are distinct and transmitted independently, such as Mendelian traits governed by single genes which express a dominant or recessive phenotype, resulting in clearly defined phenotypic groups.