How many parts to a virus?
1
2
3
4

2

Explanation:

The most simple viruses have only two parts: 1) a genome (DNA or RNA) that is a blueprint with instructions for making more viruses and 2) a capsid protein shell that protects the genome.

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: