Question

What percentage of energy is transferred from one trophic level to the next in a food chain?

• A. 1%
• B. 5%
• C. 10%
• D. 50%

Answer 1

Answer:

C. 10%

• Correct Answer: Option C - 10%

• In ecological systems, energy flows through food chains from one trophic level to the next. According to the 10% law proposed by Raymond Lindeman, only about 10% of the energy available at one trophic level is transferred to the next higher level. This occurs because a significant portion of energy (approximately 90%) is lost at each trophic level through various processes:

• Energy is used for metabolic processes (respiration)

• Energy is lost as heat

• Some parts of organisms are not consumed

• Energy is lost in excretory waste

• This 10% efficiency explains why food chains typically have only 4-5 trophic levels. As energy diminishes significantly at each step, there's not enough energy to support additional levels.

• This concept is fundamental to understanding ecological pyramids, particularly the pyramid of energy, which is always upright, showing the decrease in available energy as you move up trophic levels.

• The 10% rule is a key principle in ecology and explains why top predators are relatively rare compared to primary producers and primary consumers in most ecosystems.