Question

Producers in an ecosystem are
(A) Organisms that can be used as manures
(B) Animals in the food chain which produce more energy than they consume
(C) Animals which cause an increase in biomass by rapid multiplication
(D) Green organisms which fix solar energy by photosynthesis

Answer 1

Hint: An ecosystem is a self-regulatory and self-sustaining structural and functional unit of the landscape consisting of a community of living beings and the physical environment, both interacting and exchanging materials between them.

Complete answer:
Producers, consumers, and decomposers are all interconnected in food chains and food webs and are wholly and solely dependent on each other for their survival. The components are connected through food, contained energy, and a web of interrelationships.
Producers are the autotrophs that manufacture organic compounds from inorganic raw materials with the help of solar energy. Producers are also called transducers as they convert solar radiation into chemical energy. Besides food, producers give out oxygen and take in carbon dioxide.
Consumers are heterotrophs, mostly animals that feed on other organisms. Consumers are also called phagotrophs as they ingest food. Herbivores/First order consumers. They feed on producers. Also called key industry animals e.g Deer, Rabbit, Cattle, Goat/Sheep, Grasshopper, protozoans, molluscs. Primary carnivores/Second-order consumers. Feed on herbivores, e.g frog, wild cat, fox, snake. Secondary carnivores/Third-order consumers. Feed on primary carnivores, e.g Owl, Peacock. Top carnivores. Carnivores that are not preyed upon, e.g Lion.
Decomposers are saprotrophs which decompose the organic remains by secreting extracellular digestive enzymes. Due to the degradation of organic remains, decomposers are also called reducers. They are also known as mineralizers as they release minerals trapped in organic remains. Detritivores are decomposers, as well as scavengers. Scavengers are consumers of dead bodies, e.g vulture, carrion beetle. Parasites are consumers that feed on a small part of a living being.

So, the correct answer is option D, i,e Green organisms that fix solar energy by photosynthesis.

Note:
A food chain involves a nutritive interaction between the living organisms (biotic components) of an ecosystem. In a food chain, there occurs repeated eating i,e each group eats the other and is subsequently eaten by some other group of organisms.