Question

• nitrogen-fixing • producer • biosphere • consumer • biotic factor • heat • condensation • parasitism • commensalism • neritic zone • chlorophyll • heterotroph • invasive • mutualism • abiotic • evaporation • decomposers • Savanna • eutrophication • abiotic factor • runoff • photosynthesis• grassland
• endangered
• competition
• tundra
• carbon offsets
• desert
_____ bacteria carry out the conversion of gaseous nitrogen to a biologically useful form of nitrogen

An energy pyramid illustrates that energy in the form of _____ is lost to the surroundings as it is passed from one organism to the next

The energy role of a grizzly bear is that of a(n)
_____ because it cannot make its own food

_____ cycle nutrients from dead organisms back to the soil, where it becomes available for plants
The _____ biome is characterized by its lack of trees, warm temperatures, and moderate rainfall

Answer 1

• Nitrogen-fixing bacteria carry out the conversion of gaseous nitrogen to a biologically useful form of nitrogen
• An energy pyramid illustrates that energy in the form of heat is lost to the surroundings as it is passed from one organism to the next
• The energy role of a grizzly bear is that of a consumer because it cannot make its own food
• Decomposers cycle nutrients from dead organisms back to the soil, where it becomes available for plants
• The Savanna biome is characterized by its lack of trees, warm temperatures, and moderate rainfall

Explanation:

• The nitrogen-fixing bacteria like Azotobacter which lives in symbiotic relationship in the rhizomes of leguminous plants. They convert inorganic atmospheric nitrogen gas through the action of its enzymes like nitrogenase to organic nitrogen in the form of ammonia, which is readily assimilated by the plants.  
• In an ecosystem, at each tropic level of an energy pyramid, only 10% of energy is utilized and transferred to the next higher tropic level whereas the majority of energy is dissipated as heat during various metabolic processes.  
• Decomposers also called saprophytes like earthworms, bacteria, fungi survives on dead and decayed remains of plants and animals and also on fertilizers, pesticides etc in the soil. They recycle the nutrients by breaking down the complex biomolecules into simpler forms and release back into the soil.  
• Grizzly bears being omnivores eat both plants and animals according to their availability. Hence they are both primary and secondary consumers.
• Savanna is a grassland biome with a typical tropical wet and dry climate and receives moderate rainfall. Hence it cannot support trees but only have grasses.