Unlike what mendel observed in his pea plants, which were either tall or short, human height varies gradually over a range. why is this so?
a. multple genes contribute to human height
b. the gene controlling height is codominant
c. the gene controlling height displays incomplete dominance

A: Multiple genes contribute to human height

Explanation:

What Mendel observed in pea plants is generally considered to be exceptions to what is obtainable in most living organisms. Instead of segregating and assorting independently, a lot phenotypic expressions are as  a result of interaction of several genes on different loci (polygenic inheritance) while in some cases, multiple phenotypic expressions are controlled by a single gene.

Human height is a continuously varying character and has been studied to be controlled by multiple genes. In addition, the human height is often a result of complex interaction between genetics and the environment.

The correct answer is A.

answer:

convection currents in the magma drive plate tectonics. heat generated from the radioactive decay of elements deep in the interior of the earth creates magma (molten rock) in the aesthenosphere. the aesthenosphere (70 ~ 250 km) is part of the mantle, the middle sphere of the earth that extends to 2900 km.