Answers
Answer 1. Benthic zone is the zone of lowest levelof water such as sea or lake. Sublittoral zone is zone below the shore area whereas littoral zone is the zone near sea shore. Euphotic zone is teh zone near the surface of water where sufficient light reaches so that the maximum photosynthesis occurs and oxygen produced. The correct answer is option D.(Euphotic)
Answer 2: The plant grows in water either submerged or floating are called as hydrophytes.
The most important characteristic is they contain floating leaves and second most common characteristic is they contain aerenchyma cells. So the best answer is option d (leaves float at the surface of water).
Answer 3. Sustainability is the ability to be sustaioned or maintained at an specific speed. It also means the avoidance of depletion of natural resource for the better maintenance of ecological growth. So the correct answer is D (maintenance of a healthy environment and reasonable standard of living)
Answer 4.
During the warme season the beetle completes its two generation whereas in less warn season they are able to complete only one generation. So the higher population leads to kill more plants. Ans the corret answer is A (longer, warmer seasons have resulted in increased beetle populations)
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