Which kind of tumor grows slowly and is surrounded by membranes that prevent it from spreading from the original site?

Which of these is likely to be the best source of valid health information?

Which of the following represents a difference between viruses and viroids? a) viruses infect many types of cells, whereas viroids infect only prokaryotic cells.b) viruses have capsids composed of protein, whereas viroids have no capsids.c) viruses have genomes composed of rna, whereas viroids have genomes composed of dna.d) viruses cannot pass through plasmodesmata, whereas viroids can.

What are reasons people use tobacco