answer:
by having a high genetic level of melanin in your skin, you're skin is more protected from the ultra violet sun rays. Darker skinned races have more melanin present, these races originate from hot countries where sunlight is often present; the production of melanin in their skin allows them to reflect and inhibits they're skin from becoming extremely damaged. Light skinned races don't have a large amount of melanin due to they're native countries lacking sunlight. This is an evolutionary adaptation of the human race.
A fat girl just farted on me
Well the main purpose of xylem is to transfer sap from the roots to the leaves and phloem typically transports sugars from leaves to sink tissue. Xylem only travels up from the roots but phloem can have either travel up or down. The outside cells of xylem are dead and the the cells that make up phloem are the sieve elements, which are supported by companion cells.
Answer:
Explanation:
The physical evidence that suggest an increase in both respiratory and circulatory rate of a runner is that his/her heart beat ( pulse) iinreases significantly and the runner breathes heavily in other to let in more air into his/her body.
