What are the projections used for in viruses?

Those are calles spikes that are made usually of glycproteins. Those glycoproteins attach to receptors in the cell membrane of the host cell to trick it into letting the virus in.

the "dirty dozen" chemicals banned in an international treaty are formally known as persistent organic pollutants, or pops. the united nations environment program provided this background on what they are and what they can do to humans and wildlife.

i hope this

the second type of galaxy is called a barred spiral, which has a thing called a bar straddling the nucleus