Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
40 Cards in this Set
- Front
- Back
All of the following are characteristics associated with all living things EXCEPT:
Open Hint for Question 1 in a new window. metabolism. growth. movement. reproduction. |
movement
|
|
All of the following are general characteristics of viruses EXCEPT:
Open Hint for Question 2 in a new window. they usually contain only nucleic acid and protein. they are smaller than prokaryotes. they are acellular microbes. they are visible by light microscopy. |
they are visible by light microscopy
|
|
In the cell, mRNA is produced during the process of _____________ and utilized during the process of _____________.
Open Hint for Question 3 in a new window. transcription; translation transduction; transformation translation; transcription transcription; conjugation |
transcription; translation
mRNA molecules are produced during transcription of chromosomal genes, and they direct the translation of proteins at ribosomes. |
|
The process by which some viruses can inadvertently transfer DNA from one cell to another is called ____________.
Open Hint for Question 4 in a new window. transduction conjugation transformation transposition |
transduction
Transduction occurs when a viral capsid assembles around fragments of host DNA instead of viral DNA, setting the stage for the transfer of the host DNA to a new cell |
|
Lysozyme, an enzyme used by some viruses to attack the peptidoglycan in a bacterial cell, affects which of the following structures?
Open Hint for Question 5 in a new window. DNA cell wall ribosomes cytoplasmic membrane |
cell wall
|
|
A viral envelope is a structure composed, primarily, of a phospholipid bilayer. In this respect, a viral envelope is most similar to which of the following?
Open Hint for Question 6 in a new window. the cell wall bacterial endospores the cytoplasmic membrane ribosomes |
the cytoplasmic membrane
|
|
The number of effective antiviral drugs available is limited because
Open Hint for Question 7 in a new window. viruses use their hosts' cellular enzymes and structures to replicate. antiviral drugs cannot enter virus-infected cells. viruses replicate too quickly to be affected by antiviral drugs. viruses have different structures than bacterial or animal cells do. |
viruses use their hosts' cellular enzymes and structures to replicate.
Viruses use the host cell's machinery to replicate, thereby making the selective toxicity necessary for patient treatment difficult. |
|
The genome of an organism is its entire
Open Hint for Question 8 in a new window. nucleic acid in the nucleus. set of active genes. set of genes. genetic complement. |
genetic complement.
The genome of an organism includes its genes as well as the nucleotide sequences that connect the genes to one another - in other words, its complete genetic complement. |
|
Which of the following types of cells does NOT have a cell wall?
Open Hint for Question 9 in a new window. fungal cells animal cells algal cells bacterial cells |
animal cells
|
|
Most viruses are classified into groups of closely related genera; the taxonomic term for such a group is the __________.
Open Hint for Question 10 in a new window. phylum family order kingdom |
family
Closely related genera of any organism are grouped into a family. |
|
Which of the following scientists was the first to demonstrate that viruses are acellular?
Open Hint for Question 11 in a new window. Ivanowsky Pasteur Pauling Stanley |
Ivanowsky
In his experiments with infected tobacco plants, Ivanowsky was the first scientist to demonstrate that the cause of tobacco mosaic disease was an acellular infectious agent. |
|
The enzyme reverse transcriptase functions by making a(n) __________ copy of a(n) __________ molecule.
Open Hint for Question 12 in a new window. DNA; RNA DNA; DNA RNA; DNA RNA; RNA |
DNA; RNA
|
|
Ribosomes are responsible for the production of which of the following molecules?
Open Hint for Question 13 in a new window. tRNA polypeptides DNA mRNA |
polypeptides
The ribosome, an organelle found in all cells, synthesizes polypeptides from the information in mRNA molecules. |
|
A diploid organism has two __________.
Open Hint for Question 14 in a new window. sets of chromosomes flagella outer membranes nuclei |
sets of chromosomes
|
|
α-helices and β-pleated sheets are both associated with the structure of which of the following?
Open Hint for Question 15 in a new window. lipids nucleic acids carbohydrates proteins |
proteins
|
|
Which of the following is NOT an effective means of sterilization?
Open Hint for Question 16 in a new window. boiling water autoclaving incineration ionizing radiation |
boiling water
Incineration, autoclaving, and ionizing radiation are all regarded as effective and reliable methods of sterilization. Although boiling water can be a sterilant under certain conditions, it is not generally regarded as an effective means of sterilization. |
|
Proteins differ from one another in which of the following ways?
Open Hint for Question 17 in a new window. the types of amino acids used in their structures the sequence of their amino acids the types of bonds used to connect their amino acids the shapes involved in their secondary structure |
the sequence of their amino acids
All proteins are assembled using the same set of available amino acids, and all use peptide bonds to connect these amino acids together. Furthermore, the secondary structure of a protein is composed of α-helices and β-pleated sheets. However, proteins differ from one another in the exact sequence of amino acids used to create each protein |
|
DNA polymerase is necessary for which of the following processes?
Open Hint for Question 18 in a new window. transcription translation DNA replication and transcription DNA replication |
DNA replication
DNA replication is the process of creating a DNA copy of a DNA template. This process is accomplished by the enzyme DNA polymerase. |
|
The process by which an animal cell engulfs a substance using its cytoplasmic membrane is called
Open Hint for Question 19 in a new window. exocytosis. encephalopathy. endoflagellum. endocytosis. |
endocytosis.
|
|
Which of the following processes is used to sterilize liquids by merely trapping microbes instead of killing them?
Open Hint for Question 20 in a new window. pasteurization autoclaving filtration incineration |
filtration
The process of filtration can sterilize a liquid by trapping microbes that are too large to pass through the pores of the filter. Very small microbes such as viruses, however, can often still pass through the filter and become a source of contamination. |
|
According to the ICTV scheme of classification, viruses can be classified by a variety of characteristics, including the diseases they cause.
True False |
False
According to the ICTV scheme of classification, viruses are classified only by their type of nucleic acid, presence of an envelope, shape, and size. |
|
Which of the following types of viruses replicates in the cell's nucleus?
HIV herpesviruses rabies viruses rotaviruses |
herpesviruses
Herpes and papilloma viruses, among others, are known to replicate in the nucleus of the cell; they have a dsDNA genome very similar to the cell's genome. |
|
The _____ replication cycle in bacteriophages results in the death of the cell.
|
lytic
|
|
Viruses lack all of the following EXCEPT:
a cytoplasmic membrane. nucleic acid. cytosol. organelles. |
nucleic acid
|
|
Viruses can specifically infect one type of cell within an organism.
True False |
True
Viruses specifically infect only certain types of cells due to their interactions with molecules on the cell surface. |
|
Which of the following is a major difference between a lysogenic and a lytic cycle in bacteriophages?
Only lytic cycles can be caused by DNA-containing bacteriophages. Viral DNA is inserted into the bacterial cell only in a lytic cycle. The bacteriophage attaches to bacterial surface receptor proteins only in a lysogenic cycle. Viral DNA becomes a physical part of the bacterial chromosome only in a lysogenic cycle. |
Viral DNA becomes a physical part of the bacterial chromosome only in a lysogenic cycle.
|
|
The most common type of polyhedral capsid is a(n) _____
|
icosahedron
icosahedral capsid |
|
Which of the following terms refers to a virus in the extracellular state?
nucleocapsid virion capsid bacteriophage |
virion
|
|
Bacteriophages outnumber all other life forms.
True False |
True
Bacteriophages are more numerous than any cellular form of life |
|
Why do viruses have to infect host cells?
They cannot survive outside a host cell. They are dependent on host cell organelles and enzymes for their replication. They infect host cells in order to cause tumors. They infect host cells in order to steal the cell's genome. |
They are dependent on host cell organelles and enzymes for their replication.
|
|
A(n) _______ is a membrane that surrounds some viral capsids.
|
envelope (viral envelope)
|
|
The first virus to be identified was isolated from a
fungus. human. bacterium. plant. |
plant.
The first virus to be identified was tobacco mosaic virus, which infects tobacco plants. |
|
Viruses have genomes of DNA or RNA, but never both.
True False |
True
Viruses contain DNA or RNA, but never both |
|
Which of the following viruses creates a DNA intermediary molecule from the information in their RNA genomes?
positive-sense ssRNA viruses negative-sense ssRNA viruses dsDNA viruses retroviruses |
retroviruses
Retroviruses use reverse transcriptase to make a DNA copy of their positive-sense ssRNA genomes |
|
The capsid of a virus is made out of which of the following types of molecules?
carbohydrate lipid nucleic acid protein |
protein
|
|
Tumors that invade neighboring tissues and travel throughout the body are exhibiting a phenomenon known as _____.
|
metastasis
|
|
All of the following terms refer to viral shapes EXCEPT:
polyhedral. helical. prion. complex. |
prion.
|
|
The _____ stage of the viral life cycle is usually a spontaneous process, although in some viruses it is controlled by enzymes.
|
assembly
|
|
Proviruses become a permanent part of the host cell's genome.
True False |
True
Unlike lysogenic phages, animal viruses that engage in latency produce a provirus that becomes a permanent part of the host cell's genome. |
|
The tail fibers of a bacteriophage are most useful during which of the following stages of the lytic replication cycle?
synthesis attachment assembly entry |
attachment
Bacteriophage tail fibers help the virus attach to receptor proteins on the outside of the target cell. |