Bio 1002 Chapter 10 assignments

A _____ is a viral genome that has inserted itself into the genome of its host.

prophage

The lytic cycle of bacteriophage infection ends with the _____. replication of viral DNA entry of the phage protein coat into the host cell assembly of viral particles into phages the injection of phage DNA into a bacterium rupture of the bacterium

rupture of the bacterium

The protein coat that surrounds the nucleic acid of a virus is called a

capsid

Which of these is classified as an emerging virus that can have a direct impact on human health? Ebola lambda pneumonia tobacco mosaic virus

Ebola

Why is combination drug therapy for HIV/AIDS less likely to lead to resistance than single drug therapy? The drugs improve the immune system so that it is better able to find and remove virus particles. The likelihood of one virus spontaneously mutating to be resistant to several different drugs at the same time is extremely small. In the presence of multiple drugs, the mutation rate of HIV decreases. There are fewer side effects associated with combination drug therapy, and the appearance of resistance is directly related to the severity of side effects.

The likelihood of one virus spontaneously mutating to be resistant to several different drugs at the same time is extremely small.

A microbiologist analyzed chemicals obtained from an enveloped RNA virus—similar to a mumps virus—that infects monkeys. He found that the viral envelope contained a protein characteristic of monkey cells. Which of the following is the most likely explanation? The virus forced the monkey cell to make proteins for its envelope. The virus is a prophage. The virus gets an envelope that contains host molecules when it leaves the host cell. The virus fools its host by mimicking its proteins.

The virus gets an envelope that contains host molecules when it leaves the host cell.

Which of the following statements about viruses is FALSE? Vaccines are available to prevent several diseases caused by viruses. People can get colds and flus again because the viruses are constantly mutating. The widespread use of antibiotics has led to resistant strains of viruses. If a virus mutates, the immune system may not recognize the virus.

The widespread use of antibiotics has led to resistant strains of viruses.

Which of the following can be found in bacteria, but not viruses? proteins genetic material nucleic acids a cell membrane

a cell membrane

Suppose you were in charge of sending an unmanned space probe to a new planet in search of life. The probe would be able to collect and test samples and make observations, but the planet is too far away for the probe to be able to bring samples back to Earth. The probe is small and would only be able to run a few tests, so you want to pick a test for evidence of life that is broad enough to incorporate all forms of life as we know it. Which one of the following tests would be the best to use in this situation? a test for the presence of cells that contain DNA a test for the presence of soil suitable for growing plants a test for the presence of things that change size quickly, since it would be an indication of growth and development a test for the presence of large organisms capable of movement

a test for the presence of cells that contain DNA

Emerging viruses that infect human cells can originate from __________. a rapidly mutating lytic phage lambda viruses that were previously confined to bacterial populations that can now spread due to technological changes poor hygiene a virus spreading from one host species to humans

a virus spreading from one host species to humans

Homeostasis is a living organism's ability to maintain constant internal conditions even when environmental conditions change. ability to pump blood through the body. attempt to cool off, even when it is cold outside. ability to hibernate during cold times of the year. attempt to carry out photosynthesis even when there is no sunlight present.

ability to maintain constant internal conditions even when environmental conditions change.

A ______ is a virus that specifically infects bacteria.

bacteriophage

Which of the following is NOT a characteristic of living things? having DNA as a genetic code being capable of reproduction creating energy responding to stimuli exhibiting complex organization

creating energy

The _____ is a viral life cycle in which the virus inserts its genome into the genome of its host, where it may remain dormant for long periods.

lysogenic cycle

The phage reproductive cycle that kills the bacterial host cell is known as a _____ cycle. lysogenic transcriptional replicative lytic

lytic

The _____ is a viral life cycle that results in bursting of the host cell.

lytic cycle

Viruses are alive because they mutate and change over time through evolution. not alive because they can only carry out photosynthesis and not cellular respiration. not alive because they are not made of cells and require a host cell for reproduction. alive because they often contain DNA.

not alive because they are not made of cells and require a host cell for reproduction.

As a result of the lytic cycle, _____. the host cell is not destroyed the host cell's DNA is destroyed viral ribosomes are produced viral DNA is incorporated into host cell DNA a prophage is created

the host cell's DNA is destroyed

Viral DNA makes mRNA by the process of _____. replication infection translation lysis transcription

transcription

In the lysogenic cycle _____. host DNA is destroyed and viral DNA is replicateda bacterium replicates without passing viral DNA to its daughter cells viral DNA is destroyed and host DNA is replicated a bacterium divides once before the lytic cycle is initiated viral DNA is replicated along with host DNA

viral DNA is replicated along with host DNA

A prophage is a(n) __________. virus that infects bacteria type of retrovirus viral genome that has been incorporated into a bacterial cell's chromosome emerging virus

viral genome that has been incorporated into a bacterial cell's chromosome

Although generally not considered to be alive, a _____ is studied alongside other microbes such as bacteria.

virus