The mechanism of action of diphtheria toxin is to
A. disrupt the cell membrane
B. block nucleic acid synthesis
C. block protein synthesis
D. interfere with neurotransmission
E. destroy the cell nucleus
Ans: C. block protein synthesis
You might also like to view...
You are attempting to identify the type of helminth that has been isolated from a patient stool sample. The most important consideration to make this distinction is to
A. look at the gross anatomy to determine if the body is segmented or not. B. ask the patient about recent food and water consumption. C. determine if the cells are eukaryotic or bacterial by looking for nuclei. D. examine the sample to see if microscopic eggs are present.
The nephridium of molluscs is part of the:
a. reproductive system. b. excretory system. c. nervous system. d. digestive system. e. defense system.
A plant stem would be considered to be
a. a shoot system. b. a tissue. c. a root system. d. a meristem. e. an organ.
Nitrogen is released into the atmosphere by
a. nitrogen fixation. b. denitrification. c. nitrification. d. ammonification. e. decomposition.