What part of the cell is the most common threat to a host organism caused by invading virus

This either attaches the virus to the host cell or dissolves the membrane letting the virus into the host cell. The viral enzymes(enzymes are again chemical compounds) multiply the viral dna copies and viral protiens. These are new viruses. These new viruses breakout of the cell to infect other cells.

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.

the glands which are associated with each description is given below: