Viruses

Question 1

Viruses

Answer 1

obligate intracellular parasites that absolutely require a living host to multiply

Question 2

Distinctive features of viruses

Answer 2

(1) single type of nucleic acid- RNA or DNA- not both (2) protein coat surrounds nucleic acid (3) multiply inside living cells using host machinery (4) cause the synthesis of specialized structures that transfer nucleic acid to other cells

Question 3

Virion

Answer 3

complete viral particle with nucleic acid and coat

Question 4

Nucleic acid

Answer 4

DNA or RNA; single stranded or double stranded; linear or circular ; capsid composed of proteins; envelope composed of phospholipids, proteins and or carbohydrate spikes

Question 5

Viral Morphology

Answer 5

Non-enveloped viruses: helical and polyhedral; enveloped viruses: helical and polyhedral; different viruses infect different types of cells

Question 6

Major steps in the production of new viral particles

Answer 6

(1) attachment: receptors of the surface of the virus attach to receptors on the surface of specific cells (2) Penetration: viral particles (or a portion of it) enters the cell (3) biosynthesis of viral components (4) maturation and release