The question asks to identify a plant that traps and digests insects for nutrition. This describes a carnivorous plant. We need to evaluate each option to determine which one fits this description.
Correct Option: D) Pitcher plant is a carnivorous plant that traps and digests insects for nutrition, especially in nutrient-poor soils.
The question asks about the mode of nutrition in fungi. To answer this, we need to understand the different ways organisms obtain nutrients and identify which one applies to fungi.
C) Saprotrophic mode — Fungi are primarily saprotrophs. They secrete extracellular digestive enzymes onto dead organic matter and then absorb the resulting simple molecules. This process is crucial for decomposition in ecosystems.
The question asks to identify the bacterium responsible for nitrogen fixation in leguminous plants. This is a direct recall question from the topic of microbiology and plant-microbe interactions, specifically focusing on the nitrogen cycle.
B) Rhizobium — Rhizobium is a genus of Gram-negative soil bacteria that fix nitrogen. They form an endosymbiotic nitrogen-fixing association with roots of legumes and some other plant species. The bacteria colonize plant cells within root nodules, where they convert atmospheric nitrogen into ammonia, which is then used by the plant to synthesize proteins and other nitrogen-containing compounds.
The question asks about the substance responsible for the green color in algae. This is a fundamental concept in biology, specifically related to photosynthesis and plant pigments.
Correct Option: A) Chlorophyll is the green pigment found in algae (and plants) that is essential for photosynthesis and gives them their characteristic green color.
The question asks to identify the organisms that form a symbiotic relationship with fungi in lichens. This requires knowledge of the composition and nature of lichens.
Correct Option: A) Algae are the photosynthetic organisms that form a symbiotic relationship with fungi in lichens. They provide food through photosynthesis to the fungal partner.
The question asks for the ultimate source of energy for all living organisms. This requires understanding the fundamental energy flow in ecosystems.
Correct Option: C) The Sun is the ultimate source of energy for almost all living organisms on Earth. Through photosynthesis, plants and other producers convert solar energy into chemical energy, which then flows through various trophic levels of an ecosystem.