What is the role of gills?
a. to pump blood
b. to bring oxygen into the animal
c. to break up food
d. to be a body cavity

Nasa scientists must work together to make sure that everything is correct and accounted for when launching a shuttle. besides a physicist, what other type of scientist would be in making sure that the shuttle has the appropriate type and amount of fuel to reach its destination?

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal responds by in order to its core temperature?

What controls activities within a eukaryotic cell?