What is the purpose of a food chain?

Food chains are a pictorial description of an ecosystem: what eats what. This helps scientists track the web of interdependence. If one important component in a chain is removed or affected, we can make predictions about how this might impact the entire ecosystem. We can track the effects of disruptions on a system.

thymine. in rna, thymine is replace by uracil

answer: tributaries flow into rivers.

wetland is a biome that develops when the water gets accumulated in a land exhibiting a huge depression. these form either seasonally or permanently. the water in the wetland comes from rivers, lakes, ocean, flood, rain or other sources. the wetlands includes mangroves, marshes and peatland.

tributaries flow into the rivers develops a wetland because such water will get deposited in the depression and will restrict the original flow of tributary water. hence, water with low drainage current combines with the river water.