L1：
Lecture 1
第一题
What is the lecture mainly about?
AA type of bacterium that has an unusual life cycle
BA comparison of different types of predatory bacteria
CA research method used for studying bacteria
DA mutually beneficial relationship between two types of bacteria
第二题
What does the professor imply about most types of bacteria?
AThey replicate rapidly in lake and river water.
BThey have multiple defenses against attacks by Bdellovibrio.
CThey do not kill other bacteria.
DThey do not use a flagellum to move through water.
第三题
According to the professor, how is Bdellovibrio able to enter its target bacterium?
Select 2 answers
AIt uses its flagellum to puncture a hole in the target’s cell wall.
BIt produces enzymes to chemically break through the target’s cell wall.
CIt creates a thin biofilm that dissolves part of the target’s cell wall.
DIt spins rapidly in order to drill through the target’s cell wall.
第四题
According to the professor, what happens after Bdellovibrio enters the target bacterium cell?
AThe loss of nutrients through the opening in the cell wall kills the target bacterium.
BBdellovibrio interferes with the target bacterium’s basic cellular processes.
CThe target bacterium cell divides into new cells, each containing a Bdellovibrio.
DA chemical signal is released, causing nearby bacteria to produce protective enzymes.
第五题
Why is Bdellovibrio being investigated as a potential medical treatment?
Select 2 answers
AIt triggers the growth of new skin cells to replace damaged ones.
BIt produces a strong enzyme that might be used to break down old scar tissue.
CIt attacks the same types of germs that invade the body through cuts in the skin.
DIt destroys a type of biofilm that can damage the teeth.
第六题
What is the professor’s attitude toward the direction that Bdellovibrio research is taking?
AShe is optimistic that the results of the research will yield important benefits to society.
BShe worries that natural processes could be affected in ways that might cause more harm than good.
CShe feels that Bdellovibrio’s life cycle is too poorly understood to justify the expectations that have been raised.
DShe is surprised that it has taken scientists so long to carry out the right kinds of experiments.
