Free Man and His Environment MCQs with Answers

331. What is the niche of an organism in an ecosystem?

• A. Role played by many organisms in an ecosystem
• B. Role played by a dead organism in an ecosystem
• C. Role played by community of microorganisms in their ecosystem
• D. Role played by an organism in its ecosystem

Explanation: The niche of an organism is the role that it plays in a community, especially its living conditions and its interaction with other organisms in the community, and also its behavior and influence.

332. The distinct levels or links of food chain are called

• A. Trophic level
• B. Food web
• C. Energy pyramid
• D. Food chain

Explanation: A trophic level refers to a level or a position in a food chain, a food web, or an ecological pyramid.

333. A relationship between two or more organisms of different species in which all partners get benefit is called

• A. Symbiosis
• B. Parasitism
• C. Commensalism
• D. Predation

Explanation: Symbiosis is the interaction of two dissimilar organisms, in which both organisms benefit from the interaction.

334. Population of different species (plants and animals) living in the same habitat form a:

• A. Community
• B. Ecosystem
• C. Biosphere
• D. Microhabitat

Explanation: A community is a group of interacting species, which live in the same location.

335. Living part of ecosystem is:

• A. Lithosphere
• B. Hydrosphere
• C. Community
• D. Biosphere

Explanation: The biosphere is the part of an ecosystem which integrates all living organisms and their relationship with one another.

336. A living association between two living organisms of different species that is beneficial to both partners is called:

• A. Commensalism
• B. Parasitism
• C. Mutualism
• D. Predation

Explanation: A symbiotic relationship, or symbiosis, is a close and long-term biological interaction between two different species. The relationship can be categorized into three main types: mutualism, where both species benefit; commensalism, where one benefits and the other is unharmed; and parasitism, where one benefits at the expense of the other.

337. Individual successions are known as

• A. Primary successions
• B. Secondary successions
• C. Seres
• D. Xeroses

Explanation: The term specifically used for each individual succession in animal or plant is called seres. Therefore this is the right option here.

338. Which one of the following is the ultimate distributional unit within which a species is restrained by the limitations of its physical structure and physiology?

• A. Niche
• B. Biome
• C. Ecosystem
• D. Habitat

Explanation: The given statement is the definition of Niche given by Grinnell. Therefore opt A is the right choice here.

339. All herbivores belong to which trophic level in the food chain?

• A. T1
• B. T2
• C. T3
• D. T4

Explanation: Herbivores which are the primary consumers belong to trophic level 2.

340. How many food chains are present in the following food web?

• A. 5
• B. 3
• C. 6
• D. 4

Explanation: A series of organisms each dependent on the next as a source of food is called a food chain. Food web A system of interlocking and interdependent food chains. There are four food chains in the given food web.