Plants cannot use this component of the atmosphere directly; it must be modified by bacteria first.

oxygen

carbon dioxide

nitrogen

water vapor

Has regulatory areas for thirst, hunger, body temperature, water balance, and blood pressure

What processes take place before the mature mrna exits the nucleus?

Which line in the graph above best illustrates an effect of the carbon dioxide level in the blood on breathing rate before, during and after a period of exercise? 1.b,2.c,3.a,4.d