Daily Current Affairs Quiz: December 19, 2025

Answer: B [Only two]
Explanation:

Statement 1 is correct: Biodiversity plays a critical role in ensuring the stability of ecosystems by providing a variety of genes, species, and ecosystems that can adapt to changing environmental conditions, thus maintaining ecosystem services.

Statement 2 is correct: Decreased biodiversity can lead to an increase in zoonotic diseases as it can disrupt natural processes and lead to conditions where pathogens can more easily be transmitted to humans.

Statement 3 is correct: Each organism in an ecosystem has a specific role to play, which is referred to as its niche.

Answer: B [Only two]
Explanation:

Statement 1 is correct: In ecosystems, energy flows from the sun to producers (such as plants) and then to various levels of consumers, illustrating a unidirectional flow.

Statement 2 is incorrect: The efficiency of energy transfer between trophic levels is much lower, typically around 10%. This low efficiency is due to energy being lost as heat, used for work, or not consumed at each level.

Statement 3 is correct: Energy flow in an ecosystem is indeed unidirectional, moving from producers to consumers and not in reverse. This is a fundamental principle of ecology, highlighting the linear nature of energy transfer through food chains and food webs.

Answer: B [Only two]
Explanation:

Statement 1 is correct: Detritivores, like fungi and bacteria, decompose dead organic matter, recycling essential nutrients that support primary producers.

Statement 3 is correct: Omnivores, occupying more than one trophic level, contribute to the complexity of food webs by feeding on both producers (plants) and consumers (animals).

Statement 4 is incorrect: Terrestrial food webs can be just as complex, if not more so, than aquatic food webs. The diversity of plant and animal life on land supports intricate interactions and energy flow pathways.

Answer: C [1, 2, and 4 only]
Explanation:

Statement 1 is Correct: Abiotic components are the non-living elements of the environment, such as air, water, soil, and minerals, which provide the physical and chemical conditions necessary to sustain life on Earth.

Statement 2 is Correct: Biotic components include all living organisms—plants, animals, and microorganisms—that interact among themselves and with abiotic factors, forming ecosystems and ecological relationships.

Statement 3 is Incorrect: The atmosphere is an abiotic component, not a biotic one. Although it influences climate and weather and thereby affects living organisms, it does not consist of living entities.

Statement 4 is Correct: The hydrosphere includes all forms of water on Earth, such as oceans, rivers, lakes, groundwater, and glaciers, and is vital for both aquatic and terrestrial life.

Answer: A [1, 2 and 4 only]
Explanation:

Statement 1 is Correct: An ecological niche includes an organism’s habitat, diet, behavior, and interactions. A squirrel in an urban park faces different food sources, predators, and competition than one in a dense forest, thus occupying a different niche.

Statement 2 is Correct: Phytoplankton function as primary producers in ocean ecosystems. Through photosynthesis, they convert solar energy into chemical energy and form the base of aquatic food chains, clearly defining their ecological niche.

Statement 3 is Incorrect: Desert cacti and Arctic foxes do not occupy similar ecological niches. Although both are adapted to extreme environments, they differ fundamentally in habitat, trophic level, and ecological role, making this statement incorrect.

Statement 4 is Correct Decomposers like mushrooms occupy the niche of breaking down dead organic matter. This process recycles nutrients back into the ecosystem, maintaining soil fertility and supporting energy flow.