What is the source of energy in our ecosystem? in our ecosystem, the is the source of all energy. in terms of the ecological pyramid, of energy is passed from one level to next level.

What have we learned from fossil evidence about evolution? a) it is an abrupt change. b)the process is observable. c) it takes place during one lifetime only. d)the most complex traits are always selected.

The image below shows a common blood pressure gauge. what does this device do? a. measures the level of oxygen present in the blood b. measures the pressure of blood when the lungs expand and compress c. measures the electrical activity of the heart d. measures the pressure of blood when the heart contracts and relaxes

Which nucleotide component contains nitrogen