In leaves, excess sugar molecules may enter companion cells of phloem through ________.

A. vessel elements
B. active transport proteins
C. sieve tubes
D. perforation plates
E. pits


Answer: B

Biology & Microbiology

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Some photosynthetic euglenoids can also ingest dissolved or particulate food. Which one of the following terms would best describe such a protist?  

A.  autotrophic B.  heterotrophic C.  mixotrophic D.  osmotrophic E.  phagotrophic

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In the system of binomial nomenclature, species are assigned a two-part name: the first part is the ____ and the second

part is the ____name.

a. species; genus b. genus; species c. species; family d. genus; family e. family; species

Biology & Microbiology

Disease-causing organisms are classified as

1.fomites. 2.biological vectors. 3.mechanical vectors. 4.pathogens. 5.antigens.

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Most scientific names are derived from

a. English. b. Latin. c. Italian. d. French.

Biology & Microbiology