After 48 hours of incubation, black colonies with a dark brown halo are observed on Tinsdale agar. What type of toxin does this organism produce?
a. Emetic toxin
b. Exotoxin
c. Enterotoxin
d. Endotoxin
B
C. diphtheriae produces black colonies with a dark brown halo on Tinsdale agar and is also a potent exotoxin.
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In muscle tissue, protein consumed in the diet but not immediately used is stored as adipose tissue
A. true B. false
Figure 15.4
In step 2 (above) in the identification of the colony that contains a targeted gene, ____.
A. bacterial cells are cloned B. bacterial colonies are transferred C. bacterial cells are ruptured D. DNA is lysed E. cells with the targeted gene are identified
Respond to the following statements with reference to the five terms listed below.
A. This is the fertilized egg. B. This stage appears as a multicelled, fluid-filled ball. C. This is the division of the zygote. D. Its cellular descendants give rise to specific tissues and organs. E. This is a longitudinal series of paired segments of the mesoderm.
Transduction is the result of what mistake that viruses make during replication?
A. cutting up the bacterial chromosome B. cutting up the viral genome C. transcribing bacterial genes upon excision D. incorporating bacterial genes during phage assembly E. inserting a viral DNA fragment into the bacterial chromosome