Chapter 17 McGraw Hill
The drug azidothymidine (AZT) prevents the binding of the virus to human cells. inhibits uncoating of the viral nucleic acid. inhibits replication of the viral nucleic acid. blocks the production of capsid proteins.
inhibits replication of the viral nucleic acid.
Which of the following is the name for the prokaryotic arrangement consisting of chains of spherical cells? staphylococcus streptococcus diplococcus corynebacteria
streptococcus
The generation time of Mycobacterium tuberculosis is 30 minutes. 3 hours. 12 hours. 33 hours. 10 days.
12 hours.
If one donor cell is mixed with 20 recipient cells, eventually ________ cells will become donors. 2 5 10 15 20
20
If the virus is present as a provirus in the host cell, it remains latent and never produces new virus. True False
F
In the lysogenic stage of phage replication, the host cell is lysed. True False
F
Once a phage becomes lysogenic, it will remain lysogenic and never be lytic again. True False
F
Gram positive bacteria have flagella with four basal body rings, while those of gram negative bacteria have only two. True False
False
A spirochete moves in a screw-like manner that is mediated by axial fibrils located in the cell's periplasmic space. True False
T
In transformation, both strands of donor DNA enter the recipient cell. True False
T
West Nile virus can cause inflammation of the brain. True False
T
Where do newly produced viruses go once they are released from the infected bacterial cells? They must find a body of water to remain viable. They travel to the liver and form cysts. They must find new bacteria to infect. They enter the bloodstream and travel to the brain.
They must find new bacteria to infect.
West Nile most often affects the elderly, the very young, and those with weakened immune systems. Which of the following can you correctly infer from this statement? The elderly and very young are likely to have weakened immune systems. The elderly and young are most likely to travel to the Nile area. The elderly and young have poor hygiene. West Nile is only able to target cells of a certain age.
The elderly and very young are likely to have weakened immune systems.
Which of the following statements about antiviral interferons is FALSE? They are produced by infected host cells. They are proteins. They spread through the blood to target infected cells in other parts of the body. They stimulate production of enzymes that inhibit protein synthesis.
They spread through the blood to target infected cells in other parts of the body.
DNA transformation involves the transfer of naked DNA into pili. a recipient cell. a restriction endonuclease. a bacteriophage.
a recipient cell.
The drug _____ blocks penetration and uncoating of the _____. vidarabine; herpes virus vidarabine; influenza A virus amantadine; herpes virus amantadine; influenza A virus
amantadine; influenza A virus
Which of the following is involved in gliding motility in bacteria? axial fibrils slimy polysaccharide secretion flagella cilia
axial fibrils
During bacterial conjugation, plasmid replication occurs in the donor only. the recipient only. both the donor and recipient. either the donor or the recipient, but not both. neither the donor nor the recipient.
both the donor and recipient.
The spore layer containing peptidoglycan is the forespore. cortex. dipicolinic acid. exosporangium. protein coat.
cortex.
The mismatch repair system will repair only mismatching donor sequences. only mismatching recipient sequences. both sides of mismatching sequences. either the donor or the recipient strand
either the donor or the recipient strand.
Human Immunodeficiency Virus (HIV) presently infects about 40 million people worldwide. In what organisms did HIV originate? coldwater game fish in the ocean birds in Asia mosquitoes in the Nile swamplands monkeys in the rain forests
monkeys in the rain forests
In spore formation, the stage in which DNA condenses and aligns itself in the center of the cell is called the exosporangium. cortex. forespore. mother cell. vegetative cell.
mother cell
If the DNA of the provirus is transcribed, several single mRNA strands are produced. a plasmid is made. the provirus detaches and becomes lytic. one long polygenic mRNA is produced.
one long polygenic mRNA is produced.
When DNA from an ampicillin resistant organism is brought into an ampicillin sensitive organism by transformation and the product is grown on agar containing ampicillin, only the transformed cells will grow. only donor cells will grow. all cells grow. no cells grow. only ampicillin sensitive cells grow.
only the transformed cells will grow.
Prophage DNA is phage DNA integrated into host cell genome. phage DNA being actively expressed. phage protein left outside the bacterium. toxic to the host bacterial cell.
phage DNA integrated into host cell genome.
In the lytic cycle of phage replication, phage genes integrate into the host cell genome and are not expressed. phage genes exist as prophage. phage DNA remains inside the protein coat. phage nucleic acid is replicated and phage genes are expressed, making new phage protein and lysing the host cell.
phage nucleic acid is replicated and phage genes are expressed, making new phage protein and lysing the host cell.
Which of the following bacterial groups is described CORRECTLY? spirochetes - move by axial fibrils actinomycetes - reproduce by fragmentation nocardiae - form specialized dispersal cells on aerial mycelia mycoplasmas - rigid cell wall
spirochetes - move by axial fibrils
Retroviruses have one copy of single-stranded RNA. two copies of single-stranded RNA. one copy of double-stranded RNA. two copies of single-stranded DNA.
two copies of single-stranded RNA.
