Which animals has a heart in which oxygenated and deoxygenated blood mix?

Which list is in order from simplest to most complex? a bacteria - virus - plant - protist b protist - bacteria - virus - plant c virus - bacteria - plant - protist d virus - bacteria - protist - plant

Freckles are a dominant trait in humans. both of the girls have the genotype ff for freckles. if either one marries a man with no freckles, what are the chances that their children will have freckles?

Reactants undergo chemical reaction to form products. this chemical equation represents one such reaction. the coefficient for one of the reactants or products is incorrect. which part of the chemical equation is incorrect?