Question

which of the following is not true concerning the flow of energy through an ecosystem?
a. most solar energy is used in photosynthesis.
b. photosynthesis and cellular respiration are performed by plants.
c. not all solar energy is used for photosynthesis.
d. most of the energy from photosynthesis flows out as heat.
please select the best answer from the choices provided

Explanation:

• For option a: Only a small fraction of solar energy (about 1 - 3%) is used in photosynthesis. Most solar energy is reflected back into space, heats the atmosphere, or is used in evaporation. So, the statement "Most solar energy is used in photosynthesis" is false.
• For option b: Plants perform photosynthesis (to make food using sunlight, carbon - dioxide, and water) and cellular respiration (to break down food for energy). This statement is true.
• For option c: As mentioned above, not all solar energy is used for photosynthesis. A large part is lost as heat, reflected, etc. This statement is true.
• For option d: According to the second law of thermodynamics, most of the energy from photosynthesis (either when it is passed through trophic levels or during metabolic processes) flows out as heat. This statement is true.

Answer:

A. Most solar energy is used in photosynthesis.