<span>The blood pressure measured in the calf is lower than it is in the arm. Blood pressure in the body is highest right at the ascending arch of the aorta. From that point, the pressure decreases as blood moves "distally" from the heart. Purely mechanically, legs are farther away from the heart than are the arms, thus pressure is less.</span>
Cell wall because their has to be something protecting it.
A) One species always outcompetes the other until only one species remains.
Proteins, like steak.. ribs.. etc