Question

The total energy fixed by a green plant is called:

• A. Net Production
• B. Primary Production
• C. Secondary Production
• D. Gross Production

Answer 1

The Correct Option is D

In biology, the term "Gross Production" refers to the total energy fixed by a green plant through the process of photosynthesis. This concept is crucial in understanding how plants convert light energy into chemical energy. 

The options provided help differentiate between similar terms within ecology:

• Net Production: This is the amount of energy that remains after subtracting the energy used for respiration. It is the energy available for growth and reproduction of the plant.
• Primary Production: This refers to the energy or biomass that is produced by primary producers like plants in a given area over a certain period of time.
• Secondary Production: This is related to the energy or biomass generated by herbivores (consumers) as they consume the primary producers.
• Gross Production: The correct answer, which encompasses the total amount of energy captured by plants before any deductions for respiration.

Understanding these definitions is key for distinguishing between the energies involved at different stages of ecological and biological processes.

Answer 2

The total energy fixed by a green plant is called Gross Primary Production (GPP). GPP refers to the total amount of energy captured by plants through photosynthesis from sunlight. This is the total energy available to the plant, including the energy used for its own growth, respiration, and other metabolic processes.

Let’s look at the other options:

(1) Net Production: This refers to the energy remaining after the plant has used some of the energy for respiration. It is calculated as Net Primary Production (NPP) = GPP - Respiration. This is the energy available to the next trophic level (herbivores, for example).

(2) Primary Production: This term refers to the process of energy fixation by plants and is typically classified into Gross Primary Production (GPP) and Net Primary Production (NPP).

(3) Secondary Production: This refers to the production of biomass by consumers (such as herbivores and carnivores) in an ecosystem, not by plants.

Thus, the correct answer is (4) Gross Production, which is the total amount of energy fixed by a green plant through photosynthesis.