Biology Chapter 19
1.
Viruses can vary with respect to all of the following characteristics except _____. ( Overview) Your Answer: | the presence or absence of a membranous envelope | | Correct Answer: | the presence or absence of metabolic machinery | | No. This is a difference among viruses.
2.
A microbiologist analyzes chemicals obtained from an enveloped RNA virus that infects monkeys. He finds that the viral envelope contains a protein characteristic of monkey cells. Which of the following is the most likely explanation? ( Concept 19.1) Your Answer: | Its presence is a result of the monkey's immunological response. | | Correct Answer: | The viral envelope forms as the virus leaves the host cell. | | No. This does not explain the presence of either the envelope or the monkey protein found on the envelope.
3.
Which of the following, if any, may be a component of a virus? ( Concept 19.1) Your Answer: | single-stranded (ss) RNA | | Correct Answer: | All of the listed responses are correct. | | No. Single-stranded RNA is the genetic material of certain viruses, but there is a better answer.
4.
Viruses that infect bacteria are called _____. ( Concept 19.1) Your Answer: | capsomeres | | Correct Answer: | bacteriophages | | No. Capsomeres are the protein subunits of the capsid, the protein shell that encloses the viral genome.
5.
HIV, the virus that causes AIDS, only infects certain cells within the immune system. This is because _____. ( Concept 19.2) Your Answer: | other cells produce toxins that destroy the virus before infection can take place | | Correct Answer: | the virus binds to specific receptors that are only present on certain immune cells | | No. This is not true.
6.
Cancer cells often have protein receptor molecules on their surfaces that differ from those on normal body cells. Given this fact, how might viruses be used to treat cancer? ( Concept 19.2) Your Answer: | Viruses could be
Viruses can vary with respect to all of the following characteristics except _____. ( Overview) Your Answer: | the presence or absence of a membranous envelope | | Correct Answer: | the presence or absence of metabolic machinery | | No. This is a difference among viruses.
2.
A microbiologist analyzes chemicals obtained from an enveloped RNA virus that infects monkeys. He finds that the viral envelope contains a protein characteristic of monkey cells. Which of the following is the most likely explanation? ( Concept 19.1) Your Answer: | Its presence is a result of the monkey's immunological response. | | Correct Answer: | The viral envelope forms as the virus leaves the host cell. | | No. This does not explain the presence of either the envelope or the monkey protein found on the envelope.
3.
Which of the following, if any, may be a component of a virus? ( Concept 19.1) Your Answer: | single-stranded (ss) RNA | | Correct Answer: | All of the listed responses are correct. | | No. Single-stranded RNA is the genetic material of certain viruses, but there is a better answer.
4.
Viruses that infect bacteria are called _____. ( Concept 19.1) Your Answer: | capsomeres | | Correct Answer: | bacteriophages | | No. Capsomeres are the protein subunits of the capsid, the protein shell that encloses the viral genome.
5.
HIV, the virus that causes AIDS, only infects certain cells within the immune system. This is because _____. ( Concept 19.2) Your Answer: | other cells produce toxins that destroy the virus before infection can take place | | Correct Answer: | the virus binds to specific receptors that are only present on certain immune cells | | No. This is not true.
6.
Cancer cells often have protein receptor molecules on their surfaces that differ from those on normal body cells. Given this fact, how might viruses be used to treat cancer? ( Concept 19.2) Your Answer: | Viruses could be