Question: 100% NCERT covered from Particular Keyword.Explanations are 100% from NCERT | [Difficult level: Easy] From NCERT NEET Derived Question.
Consider the following statements:
I. In an aquatic ecosystem, GFC is the major conduit for energy flow.
II. In a terrestrial ecosystem, DFC is the major conduit for energy flow.
III. GFC and DFC are not interconnected at any level.
Which of the above statements are true?
1. I and II only
2. I and III only
3. II and III only
4. I, II, and III
Answer: 1. I and II only
In an aquatic ecosystem, GFC is the major conduit for energy flow.
As against this, in a terrestrial ecosystem, a much larger fraction of energy
flows through the detritus food chain
👉Except for the deep sea hydro-thermal ecosystem, sun is the only source
of energy for all ecosystems on Earth
👉Of the incident solar radiation less
than 50 per cent of it is photosynthetically active radiation (PAR).
👉Plants
capture only 2-10 per cent of the PAR
👉plants and photosynthetic bacteria (autotrophs)
👉In a terrestrial
ecosystem, major producers are herbaceous and woody plants.
👉Likewise,
producers in an aquatic ecosystem are various species like phytoplankton,
algae and higher plants.
👉Some common herbivores are insects, birds and mammals in terrestrial
ecosystem and molluscs in aquatic ecosystem.
👉A simple grazing food chain (GFC) is depicted
below:
Grass→ Goat→ Man:
(Producer) →(Primary Consumer)→ (Secondary consumer
👉The detritus food chain (DFC) begins with dead organic matter. organisms include mainly
fungi and bacteria.
These are also known as
saprotrophs (sapro: to decompose).
👉In an aquatic ecosystem, GFC is the major conduit for energy flow.
As against this, in a terrestrial ecosystem, a much larger fraction of energy
flows through the detritus food chain
👉Detritus
food chain may be connected with the grazing food chain at some levels
👉omnivores:
These natural interconnection of food chains make it a food web.
👉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
👉Do you think there is any such limitation in a detritus food chain?
Answer:
There is no limitation in detritus food chain for number of trophic level because 10% rule is not applicable and high magnitude of energy
Question: 100% NCERT covered from Particular Keyword.Explanations are 100% from NCERT | [Difficult level: Easy] From NCERT NEET Derived Question.
The detritus food chain (DFC) begins with________________. It is made up of decomposers which are ______________organisms, mainly________________. They meet their energy and nutrient requirements by degrading ______________.
1. detritus, heterotrophic, earthworm and dead organic matter.
2. dead organic matter, heterotrophic, fungi and bacteria, dead organic matter.
3. dead organic matter, autotrophic, fungi and plants, dead organic matter.
4. grass, heterotrophic, fungi and bacteria, dead organic matter.
Answer:2. dead organic matter, heterotrophic, fungi and bacteria, dead organic matter.
