Chapter 22: Viral Replication and Taxonomy

Question 1

Viruses have 4 unique characteristics:

1. ) They are __________. They simply float around until they come in contact with an appropriate cell.
2. ) They are basic life forms composed of a protein coat called a ______, that surrounds genetic material. Viruses do not have organelles or ribosomes. Certain viruses are further enclosed by an external lipid bilayer membrane that surrounds the capsid and may contain glycoproteins. Some viruses also carry some structural proteins and enzymes inside their capsid.
3. ) The genetic material is either ___ or ___, never both. The genetic material contains instructions to make millions of clones of the original virus.
4. ) Replication of the genetic material occurs when the virus takes control of the host cell’s _________ _________. Viruses contain all of the genetic information, but not the _______ needed to build millions of replicas of the original virus.

Answer 1

energy-less

capsid

DNA or RNA

synthetic machinery

enzymes

(p. 220)

Question 2

Viruses are classified as either DNA or RNA. Of course, nothing can ever be quite that simple. The nucleic acid strands can be ______-_________, ______-_________ linear, or looped, in separate segments or one continuous strand. The nucleic acid sequences can encode a simple message or encode hundreds of enzymes and structural proteins.

Answer 2

single-stranded
double-stranded

(p. 220)