The correct answer is (a). Energy flow in the biospheric ecosystem is unidirectional.
Energy flow in an ecosystem is the movement of energy from one organism to another. The sun is the ultimate source of energy for all ecosystems. Plants use the sun’s energy to create food through photosynthesis. Animals eat plants or other animals to get energy. When an organism dies, its energy is released back into the ecosystem through decomposition.
Energy flow in an ecosystem is unidirectional, meaning that it flows in one direction only. The sun’s energy is used by plants to create food, which is then eaten by animals. The animals’ waste products and dead bodies are then decomposed, releasing the energy back into the ecosystem. However, the energy that is released during decomposition is not as much as the energy that was originally used by the plants. This is because some of the energy is lost as heat during the process of photosynthesis.
The loss of energy at each trophic level is known as the 10% rule. This rule states that only about 10% of the energy from one trophic level is transferred to the next trophic level. This is because some of the energy is lost as heat during the process of digestion. The remaining 90% of the energy is lost as heat or used for other purposes, such as growth and reproduction.
The 10% rule is important because it limits the number of trophic levels that can exist in an ecosystem. If there were too many trophic levels, there would not be enough energy to support all of the organisms. This is why most ecosystems have only four or five trophic levels.
The 10% rule also explains why top predators are often rare. Top predators are at the top of the food chain and they only get a small amount of energy from the organisms below them. This means that they need to eat a lot of food to survive. As a result, top predators are often very large and they have a slow metabolism.
(b) Energy flow in the biospheric ecosystem is cyclic. This is not correct because energy flow in an ecosystem is unidirectional.
(c) Relative loss of energy in natural ecosystem decreases with increasing trophic levels. This is not correct because the 10% rule states that only about 10% of the energy from one trophic level is transferred to the next trophic level.
(d) Species at progressively higher tropic levels appear to be less efficient, in using available energy. This is not correct because the 10% rule states that only about 10% of the energy from one trophic level is transferred to the next trophic level. This means that all species, regardless of their trophic level, are equally inefficient at using available energy.