It depicts the numbers of individual organisms at different trophic levels of the food chain.
It is helpful to calculate the changes observed in the number of organisms in each trophic level.
An upright pyramid of numbers, the number of individuals decreases from the lower level to the higher level.
This type of pyramid is usually found in the grassland ecosystem and the pond ecosystem.
T
he grass in a grassland ecosystem occupies the lowest trophic level because of its abundance
We can identify which level is in the endangered zone and need to be saved. But its limitation is we cannot count a number of all organisms accurately.
1. In a pyramid of biomass, the weight (biomass) of all individuals in each trophic level is considered instead of counting the number of individuals. This gives a more accurate representation of the energy available in each trophic level, as larger organisms typically have more energy stored in their tissues.
2. The pyramid of biomass is structured with producers at the bottom, representing the largest amount of biomass in the ecosystem. Producers (e.g., plants) convert sunlight into energy through photosynthesis and form the base of the food chain. As energy transfers up the trophic levels through consumption, energy is lost in the form of waste and heat, resulting in a decrease in biomass as you move up the pyramid. This is why the biomass of producers is at the bottom of the pyramid, as they represent the largest amount of available energy in the ecosystem.
Understanding the Statements The statements provided relate to ecological pyramids, specifically biomass and energy pyramids in terrestrial and aquatic ecosystems. Let's evaluate each statement individually. Statement 1: Pyramid of Biomass in Terrestrial Ecosystems - In most terrestrial ecosystems, the pyramid of biomass indeed has a large base of primary producers (plants) at the bottom, supporting smaller biomass at higher trophic levels (herbivores and carnivores). - This statement is correct as it reflects the typical structure of terrestrial food webs. Statement 2: Inverted Pyramid of Biomass in Aquatic Ecosystems - In many aquatic ecosystems, particularly in those with high turnover rates (like phytoplankton), the biomass pyramid can be inverted. - Here, the biomass of primary producers (phytoplankton) may be less than that of the higher trophic levels (zooplankton and fish), especially when considering seasonal changes. - This statement is also correct. Statement 3: Inverted Energy Pyramid - While energy pyramids are typically not inverted because energy is lost at each trophic level (usually about 90% loss), there are rare conditions where they can appear inverted, depending on specific ecological dynamics. - However, this is uncommon and generally not accepted as a standard characteristic of energy flow in ecosystems. - Hence, this statement is somewhat misleading and not typically regarded as correct. Conclusion Based on the evaluations: - Statements 1 and 2 are correct. - Statement 3 is misleading regarding the general principles of energy flow. Thus, the correct answer is option B: 1 and 2 Only.
Chapter doubts & questions for Functions of an Ecosystem - Environment & Additional Topics for State PSC Exams 2025 is part of BPSC (Bihar) exam preparation.
The chapters have been prepared according to the BPSC (Bihar) exam syllabus.
The Chapter doubts & questions, notes, tests & MCQs are made for BPSC (Bihar) 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises,
MCQs and online tests here.
Chapter doubts & questions of Functions of an Ecosystem - Environment & Additional Topics for State PSC Exams in English & Hindi are available as part of BPSC (Bihar) exam.
Download more important topics, notes, lectures and mock test series for BPSC (Bihar) Exam by signing up for free.