Question

Choose the correct option from the below about food chain:

• A. The flow of energy is not unidirectional in the food chain.
• B. The size of any food chain is usually restricted to 3-5 trophic levels.
• C. For food chains to sustain, the inorganic nutrients must keep circulating.
• D. As the trophic levels increases, the size of the population decreases.

Answer 1

Answer: (A), (B), (C)

For food chains to sustain, the inorganic nutrients must keep circulating.

The correct options are A, B, and C:

Explanation of the correct option:

Option A:

1. Due to the fact that the sun is the only energy source for all terrestrial ecosystems, the energy flow in the food chain is unidirectional.
2. After that, the energy that the autotrophs have gathered does not return to the sun.
3. As a result, energy in the food chain progresses through different trophic levels.
4. Three to five trophic levels make up the food chain, which is upright and straight. Only 10% of energy is transmitted from one trophic level to another; the remaining 90% is used by the body to produce heat and metabolism.

Option B:

1. There are only 4-5 trophic levels in each food chain because only 10% of energy is transferred from one trophic level to the following one up. After four or five trophic levels, very little useful energy is left since the loss of energy at each level is so significant.
2. The producers, or green plants, are found on the first and lowest level.
3. The second-level creatures, herbivores, or plant eaters, eat the plants or their products.
4. Primary carnivores, or meat eaters, consume herbivores at the third level, while secondary carnivores consume primary carnivores at the fourth level.

Option C:

1. Water and minerals are two typical inorganic nutrients. Because they come from non-living sources and lack carbon, water and minerals are both regarded as inorganic.
2. Water is maybe the second most essential element for life after carbon.
3. Water is important for all organisms as well as the producer(plants) to survive and minerals which can be macro or micro are necessary for plant growth as well as for other cycles occurring in the food chain.

Explanation of the incorrect options:

Option D:

1. Higher trophic levels often have fewer creatures since there is less energy there.
2. At higher trophic levels, organisms are often greater in size, but because there are fewer of them, there is less biomass produced. The total mass of all trophic level creatures is known as biomass.
3. All trophic levels may die out, upsetting the balance of that ecosystem, also known as homeostasis, if one trophic level's population increases or decreases too much.
4. This can reduce the number of producers and, in turn, reduce the amount of energy available in the food web, causing a population crash.

Final Answer: The correct statements about the food chain are the flow of energy is not unidirectional in the food chain, the size of any food chain is usually restricted to 3-5 trophic levels, and for food chains to sustain, the inorganic nutrients must keep circulating.