The question asks for the definition of plankton. To answer this, one needs to recall the basic biological classification of organisms in aquatic environments.
Correct Option: A) Floating organisms in aquatic ecosystems
This option accurately describes plankton. They are a diverse group of organisms (including phytoplankton, which are plant-like, and zooplankton, which are animal-like) that live in aquatic environments and are unable to swim effectively against water currents, hence they "float" or drift.
The question asks to identify the organisms included in phytoplankton. Phytoplankton are microscopic organisms that live in water and perform photosynthesis. Understanding their characteristics and typical examples will help in selecting the correct option.
Correct Option: C) Microscopic plants including algae and some bacteria. This option correctly identifies the broad group of organisms that constitute phytoplankton, emphasizing their microscopic nature and photosynthetic capability, including various forms of algae and certain bacteria.
The question asks to identify which of the given animals are mammals. To answer this, we need to recall the classification of each animal mentioned: Sea cow, Sea Horse, and Sea lion.
Based on this classification, both Sea cow and Sea lion are mammals, while Sea Horse is a fish.
Correct Option: B) 1 and 3 only
The question asks about the percentage of oxygen produced by phytoplankton relative to all plants. This is a factual question related to environmental science and biology, specifically the role of marine organisms in global oxygen production.
Correct Option: C) 60% — Phytoplankton are responsible for producing approximately 50% to 70% of the oxygen in the Earth's atmosphere. The option 60% is a commonly cited figure and falls within this accepted range, making it the most accurate answer among the choices.
UPSC - 2015
The question asks about the managing body of the 'BioCarbon Fund Initiative for Sustainable Forest Landscapes'. This is a factual question related to international environmental initiatives and the organizations that manage them. Identifying the correct international financial institution or environmental program is key.
Correct Option: D) World Bank
To answer this question, we need to understand the basic requirements for phytoplankton growth. Phytoplankton are photosynthetic organisms, which means they require sunlight to produce energy. We then need to consider where sunlight penetrates in the ocean.
Correct Option: C) All lighted regions including Polar Regions
Phytoplankton require sunlight for photosynthesis. Therefore, they are found in all parts of the ocean where light penetrates sufficiently, which is known as the euphotic or photic zone. This zone exists from the equatorial regions to the polar regions, especially during the seasons when sunlight is available (e.g., summer in polar regions).