Ads for tobacco and alcohol products often target teens, what messages do these ads try to send to these groups?
a. these drugs can cause health problems
b. these drugs can get in the way of future goals
c. these drugs are illegal for teens to use and buy
d. these drugs are used by attractive, popular people

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.