With reference to Grazing Food Chain (GFC) and Detritus Food Chain (DFC), consider the following statements: A) GFC begins with producers while DFC begins with dead organic matter. B) In a terrestrial ecosystem, a larger fraction of energy flows through the GFC than through the DFC. Which of the statements given above is/are correct?

• The Grazing Food Chain (GFC) begins with producers (green plants) while the detritus food chain (DFC) begins with dead organic matter. Hence statement 1 is correct.

GFC

• In GFC the producers are consumed, directly or indirectly, by consumers.
• If they feed on the producers, the plants, they are called primary consumers, and if the animals eat other animals which in turn eat the plants (or their produce) they are called secondary consumers. Likewise, you could have tertiary consumers too.
• The consumers that feed on these herbivores are carnivores, or more correctly primary carnivores (though secondary consumers).
• Those animals that depend on the primary carnivores for food are labeled secondary carnivores.

DFC

• The DFC is made up of decomposers which are heterotrophic organisms, mainly fungi, and bacteria.
• They meet their energy and nutrient requirements by degrading dead organic matter or detritus. These are also known as saprotrophs (sapro: to decompose).
• Decomposers secrete digestive enzymes that break down dead and waste materials into simple, inorganic materials, which are subsequently absorbed by them.
• 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 DFC than through the GFC. Hence statement 2 is not correct.