Question: 100% NCERT covered from Particular Keyword.Explanations are 100% from NCERT | [Difficult level: Easy] From NCERT NEET Derived Question.
Consider the following four statements (A–D), select the correct option stating which ones are true (T) and which ones are false (F)
(A) Organism at each trophic level depends on those at higher trophic levels for their energy demands.
(B) Each trophic level has a certain mass of living material at a particular time called standing crop.
(C) The amount of inorganic matter present in an ecosystem at a given time called standing state.
(D) The number of trophic levels in a grazing food chain is not restricted
A B C D
1. T T F F
2. F T F T
3. T F T F
4. F T T F
Answer:4. F T T F
👉You must have heard about the scourge of the water bodies or about
the ‘terror of Bengal’. This is nothing but the aquatic plant ‘water hyacinth’
which is one of the most invasive weeds found growing wherever there is
standing water.
👉Each trophic level has a certain mass of living material at a particular
time called as the standing crop.
👉The standing crop is measured as the
mass of living organisms (biomass) or the number in a unit area.
👉The
biomass of a species is expressed in terms of fresh or dry weight.
Measurement of biomass in terms of dry weight is more accurate.
👉The number of trophic levels in the grazing food chain is restricted as
the transfer of energy follows 10 per cent law – only 10 per cent of the
energy is transferred to each trophic level from the lower trophic level
👉Inverted pyramid of biomass-small standing crop of phytoplankton supports large
standing crop of zooplankton
👉The
amount of nutrients, such as carbon, nitrogen, phosphorus, calcium, etc.,
present in the soil at any given time, is referred to as the standing state
👉The movement of nutrient elements through the various components of
an ecosystem is called nutrient cycling. Another name of nutrient cycling
is biogeochemical cycles (bio: living organism, geo: rocks, air, water).
Nutrient cycles are of two types: (a) gaseous and (b) sedimentary
👉sedimentary cycle (e.g., sulphur and
phosphorus cycle)
