Consider all organisms that have circulatory systems similar to those of humans. Is there any "ideal" proportion between the sizes of the circulatory system and the entire organism? How does this ratio affect the efficiency of the organ system?

The dynamics of the cellular and molecular constituents of the circulatory system are regulated by the biophysical properties of the heart, vasculature and blood cells and proteins. In this review, we discuss measurement techniques that have been developed

Explanation:

not necessarily. higher fitness requires the organism to be reproductive successful. for example, an organism at age 10 with 15 offspring is much more fit than an organism at age 15 with only 5 offspring.

you know they are heterozygous for a trait because they have it as jj or jj.