Whats the meaning the health symbol?

How do the uv rays cause damage?   what exactly causes the skin to burn;   can you be more specific about this mechanism?   3. how do photosensitive medications increase a person's sensitivity to sunlight and therefore increase their risk of getting burned?     what kind of medications can increase photo-sensitivity, can you think of some examples?

If babies are consistently placed on their backs without any restrictions, what will happen to their development? a. they suffer from weakness in certain muscle groups. b. their ability to roll over, crawl, and eventually walk is hindered. c. they suffer brain damage from the pressure on the back of the head. d. they learn to roll over, crawl, and eventually walk on their own.

Which stage of stress includes the fight or flight response?