Why are certain amino acids called essential amino acids? a. because they are available in abundance b. because they are not manufactured by the body c. because they can form bonds with any molecule d. because they are the most stable among all the amino acids e. because they are needed for the formation of all biomolecules?

How does natural selection change thephenotypes within a population over time?

What type of competition exsist between two species. turtles and fish

4. if a cell is placed inside a solution that has a higher concentration of solute than on the inside of the cell, what can be said about the movement of water? a. water will move out of the cell, causing it to shrivel. b. water will move in and out of the cell at the same rate. c. water will move out of the cell, causing it to swell. d. water will move into the cell, causing it to swell.