DNA is comprised of four different types of . Each one is made up of a pentose , a group, and one of four . 2. Adenine, guanine, cytosine and thymine are . 3. Adenine and guanine, which have a nine-member double-ring, are called . 4. Cytosine and thymine, which have a six-member single-ring, are called .

1)  Nitrogenous bases

2) Nucleotides

3) Purines

4) Pyrimidines

Explanation:

1) Each one is made up of a pentose , a group, and one of four Nitrogenous bases

2) Adenine, guanine, cytosine and thymine are Nucleotides

3. Adenine and guanine, which have a nine-member double-ring, are called Purines

4. Cytosine and thymine, which have a six-member single-ring, are called Pyrimidines

answers are:

lysogenic     viral dna merges with host cell dna

lysogenic     no symptoms

lytic               viral dna takes over

lysogenic     virus does not destroy host cell

lytic               virus destroys host cell

lytic               induces symptoms of viral infection

lysogenic       cell reproduces and spreads provirus