In what situation is having a lot of melanin usetul and in what situation is having less melanin useful

The phlogiston theory in the 17th century attempted to explain burning. the theory stated that combustable objects contained a material called phlogiston, a substance without mass, color, odor, etc. after objects burned, the objects were dephlogistonated and were then in their true form. the phlogiston theory was accepted until the 18th century, when lavoisier proved that combustion requires a gas that has mass. phlogiston is considered a) to be scientific knowledge b) not to be scientific knowledge c) to be proven by scientific method d) to be accepted in the modern scientific community

Hey me with this one❤☺❤ how do you say that a cell also has a life span and death like an organism? give one example.

Works together in the synthesis, modification, packaging, and transport of lipids and proteins