Briefly discuss the importance of lichens in nature. Briefly discuss the importance of algae in nature.
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By what means are helminthic parasites transmitted to humans?
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Verified Solution
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Key Concepts
Helminthic Parasites
Transmission Routes
Preventive Measures
Why is it significant that Trichomonas does not have a cyst stage? Name a protozoan parasite that does have a cyst stage.
The definitive host for Plasmodium vivax is
a. human.
b. Anopheles.
c. a sporocyte.
d. a gametocyte.
Differentiate the terms in each of the following pairs:
a. etiology and pathogenesis
b. infection and disease
c. communicable disease and noncommunicable disease
Using the following data, draw a graph showing the incidence of influenza during a typical year. Indicate the endemic and epidemic levels. <IMAGE>
The emergence of new infectious diseases is probably due to all of the following except
a. the need of bacteria to cause disease.
b. the ability of humans to travel by air.
c. changing environments (e.g., flood, drought, pollution).
d. a pathogen crossing the species barrier.
e. the increasing human population.