Transfer of material and energy from one ecosystem to other ecosystem is best examplified by

Identify the possible link “$A$” in the following food chain.

Plant $→$ Insect $→$ Frog $→$ “$A$” $→$ Eagle

Herbivores are called

Which of the following are the essential sources for releasing in the atmosphere?

$I.$ Burning of wood

$II.$ Volcanic activity

$III.$ Combustion of organic matter

$IV.$ Fossil fuels

Choose the correct option

The trophic level of Cuscuta, Orobanche and Albugo is

Consider the following four statements $(A-D)$ and select the correct option stating which ones are true $(T)$ and
which ones are false $(F)$.
Statements :
$(A)$ Vertical distribution of different species occupying different levels in a community is called stratification.
$(B)$ Net primary productivity minus respiration losses is the gross primary productivity.
$(C)$ Rate of biomass production is called decomposition
$(D)$ Annual net primary productivity of oceans is $55$ billion tons