Where does the water that we use to meet our everybody needs come from

Melanocytes and keratinocytes work together in protecting the skin from uv damage when keratinocytes a. provide the melanocyte with a protective shield against abrasion b. maintain the appropriate temperature so the product of the melanocyte will not denature c. maintain the appropriate ph in order for the melanocyte to synthesize melanin granules d. accumulate the melanin granules on their superficial portion, forming a uv-blocking pigment layer

(i think the answer is a, am i right? ) most regulatory signs are a. octagonal and red or white b. circular and blue or green c. rectangular and red or white d. rectangular and yellow

The pleural cavity contains the a brain heart lungs spine