Question

Matter and energy flow through the biosphere. The flow of matter, however, differs from the flow of energy. Which of the following statements accurately describes these differences?

A) Matter flows in cycles, whereas energy flows in one direction.
B) Matter does not accompany energy as it enters the biosphere, but it does flow with energy from the biosphere.
C) Energy flows from chemotrophs to phototrophs, whereas matter flows from phototrophs to chemotrophs.
D) Energy flows as organic molecules are reduced to inorganic molecules, but matter does not.
E) Matter and energy flow sometimes in cycles and sometimes unidirectionally.

Answer 1

Matter flows in cycles, whereas energy flows in one direction through the biosphere.

Step-by-step explanation:

Matter and energy flow through the biosphere in different ways. Energy flows in a unidirectional manner, entering ecosystems as sunlight or inorganic molecules and leaving as heat. On the other hand, matter flows in cycles. The six most common elements associated with organic molecules, such as carbon and nitrogen, take a variety of forms and are recycled between living organisms and the nonliving environment in a process called a biogeochemical cycle.

For example, carbon is found in all organic molecules and forms the basis of life. It cycles between plants, animals, and the atmosphere through processes like photosynthesis and respiration. Similarly, nitrogen is an important component of nucleic acids and proteins, and it cycles through the atmosphere, soil, and organisms.

Therefore, option A is the correct answer: Matter flows in cycles, whereas energy flows in one direction.