The hormone that stimulates the reabsorption of sodium and water in the kidney is: MCQ with Answer and Explanation

Explanation:
Taxonomy is the branch of science concerned with the classification, identification, and naming of organisms. It involves arranging organisms into hierarchical categories based on their shared characteristics and evolutionary relationships. The study of tissues is Histology, and the study of fossils is Paleontology.

Explanation:
Azolla is an aquatic fern that harbors the nitrogen-fixing cyanobacterium Anabaena azollae in its leaf cavities. It is extensively used as a biofertilizer in rice paddies, adding organic nitrogen. Rhizobium fixes nitrogen in legume roots, Azotobacter is free-living in soil, mycorrhiza is a fungal association enhancing phosphorus uptake. Azolla multiplies rapidly and improves soil fertility.

Explanation:
Rhizobium species infect legume roots, leading to root nodule formation, where they fix atmospheric N₂ into ammonia using nitrogenase enzyme. They are symbiotic, receiving carbohydrates from the plant. Azotobacter and Clostridium are free-living nitrogen fixers. Nitrosomonas is a nitrifying bacterium. Legume-Rhizobium symbiosis is crucial in sustainable agriculture, reducing the need for nitrogen fertilizers.