Which of the following is (are) true about viruses?
a. Viruses are classified below the cellular level of biological organization.
Which of the following is not a reason scientists suspected that something other than bacteria was the cause of tobacco mosaic disease?
b. Treating infectious sap with alcohol failed to remove the infectious agent.
A researcher lyses a cell that contains nucleic acid molecules and capsomeres of tobacco mosaic virus (TMV). The cell contents are left in a covered test tube overnight. The next day this mixture is sprayed on tobacco plants. Which of the following would be expected to occur?
c. The plants would develop the typical symptoms of TMV infection.
Viruses are referred to as obligate parasites because
d. the enzymes produced by the virus before it infects the cell.
Which of the following is characteristic of the lytic cycle?
D) A large number of phages is released at a time.
Which of the following statements about the lysogenic cycle of lambda ( . phage is incorrect?
C) The phage genome replicates along with the host genome.
Virulent phages undergo a(n) ____ life cycle, whereas temperate phages are capable of undergoing a(n) ____ cycle.
c. lytic; lysogenic
What is the function of the single-stranded RNA in certain animal viruses?
D) A and C only are correct.
Viruses with single-stranded RNA that acts as a template for DNA synthesis are known as
Viral envelopes contain proteins with covalently attached carbohydrate groups called