Describe the pattern of inheritance that is most likely associated with a mutation in the MT-ND5 gene. Explain why individuals are not typically heterozygous with respect to mitochondrial genes.

this gene is a mitochondrial gene and therefore it is maternally inherited

Explanation:

The MT-ND5 gene is a gene of the mitochondrial genome that provides instructions for synthesizing a protein called NADH dehydrogenase 5, which is part of the complex I (the first enzyme of the respiratory chain). In most multicellular organisms, the mitochondrial DNA (mtDNA) is inherited from the mother (i.e., maternally inherited), whereas nuclear DNA (i.e., nuclear genome) is inherited equally from both parents. For example, mitochondria in human sperm are usually destroyed after fertilization. In consequence, mitochondrial mutations are transmitted by maternal inheritance, and individuals, therefore, cannot be heterozygous for mitochondrial genes.

answer: substrate concentration. enzymes work best when there is a high enough substrate concentration for the reaction they catalyse.