Which of the following statements concerning gene is/are true? Select all that apply. Check All That Apply
A gene is a segment of DNA that determines a certain trait.
An allele is a variation of a given gene.
Genes contain information that codes only for proteins involved in the regulation of gene expression

answer; i believe that the correct answer is ; males are hemizygous for the x chromosome;

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.

the correct answer is 2 and 4