This type of natural selection is referred to as directional selection. In this type of natural selection, either one phenotype is preferred or the other; therefore, there is no equilibrium between the populations of the phenotypes that are present.
Examples of organisms that have undergone directional selection are black bears during the ice ages, African chichlid and sockey salmon.
The correct answer is "active transport is ATP dependent whereas in passive transport molecules use kinetic energy to move across the membrane." in active transport cells use molecules embedded on the cell membrane called carriers in the presence of energy. cells use energy and carriers because molecules must move against concentrated gradient inside the cell. on the hand, passive transport is a process by which molecules move from the region of high concentration to the region of low concentration across plasma membrane until balance is obtained on both sides of the membrane. once equilibrium has been achieved in passive transport the movement of molecules stops.
Answer:
make me brainest
Explanation:
the heart , blood, blood vessels form the circulatory system