Testosterone is an example of a chemical signal that affects the cells that synthesize it, the neighboring cells in the testis, along with distant cells outside of the testis. thus testrosterone is an example of

Which system revise and send electrical signals throughout the body

Use the phylogenetic tree to the right to determine which statement below is true. organisms a and f are not related. organism e is more closely related to organism b than organism f. organisms c and d are more closely related than organisms a and b. phylogenetic trees

Select all that apply genes are specific nucleotide sequences occur in numbers that are the same as the number of chromosomes are located in a specific place on a chromosome determine the traits of an organism are units of rna