NEET Zoology - MCQ Practice Questions

Carrying capacity (K) is the maximum population size an environment can support with available resources without degradation.

CO₂ is the major anthropogenic greenhouse gas, comprising about 76% of total greenhouse gas emissions, contributing significantly to global warming.

Transpiration is the release of water vapor by plants through stomata in leaves. Evaporation refers to water bodies.

Disease transmission increases with population density, making it a density-dependent factor. Natural disasters are density-independent.

In a forest, one large tree (producer) supports many insects and parasites, creating an inverted pyramid of numbers.

Fungi are primary decomposers that break down dead organic matter. Earthworms are detritivores, not true decomposers.

CFCs from refrigerants and aerosols release chlorine atoms that catalytically destroy ozone molecules in the stratosphere.

Coal is a non-renewable fossil fuel formed over millions of years. Solar, wind, and geothermal are renewable resources.

Biodiversity hotspots are regions with high concentration of endemic species and exceptional species diversity, like Western Ghats in India.

The Western Ghats is one of the world's 34 biodiversity hotspots with over 7,400 species of plants, many endemic to the region.

Secondary succession occurs after disturbance to an existing ecosystem where soil remains intact, allowing faster recovery.

This law states that two species competing for identical resources in the same habitat cannot coexist; one will be outcompeted.

Mutualism benefits both organisms. Nitrogen-fixing bacteria receive carbohydrates from legumes while providing usable nitrogen.

Understanding ecological terms and their definitions

Step 1: Analyze each option

Step 2: Match the key phrase "varies in different environmental contexts"

The question emphasizes that a species' role CHANGES depending on conditions — this is the ability to adapt and shift function, not a fixed characteristic. This is plasticity/versatility.

Step 3: Example confirmation

A generalist species like a crow eats different foods in different habitats (urban vs. rural) — demonstrating ecological plasticity, not fixed niche breadth.

Answer: (D) Ecological plasticity or ecological versatility

Jim Corbett National Park (originally Hailey National Park) in Uttarakhand was India's first national park, established to protect tigers.

Biomagnification is the process where persistent pollutants like DDT accumulate in higher concentrations as you move up the food chain.

Phytoplankton are autotrophic organisms that produce their own food through photosynthesis, making them primary producers in aquatic ecosystems.

The 10% law indicates that only about 10% of energy available at one trophic level is transferred to the next level, with the rest lost as heat and through metabolic processes.

Disease spread increases with population density, making it a density-dependent factor. Natural disasters are density-independent factors.

Secondary succession occurs on previously colonized areas where soil remains intact, such as after a fire. Primary succession occurs on bare rock or new land.