Which of the following is (are) essential element(s)
in ecosystems?
a. oxygen
b. hydrogen
c. carbon
d. nitrogen
e. all of these
Answer: e
Biology & Microbiology
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In electron transport systems, the electron carriers are membrane associated
Indicate whether the statement is true or false.
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All of the genes in a population comprise its
A) genotype. B) gene pool. C) gene reservoir. D) genome.
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The structure indicated by the letter "C" above
represents a. actin. b. myofibril. c. myosin. d. myofilament. e. muscle fiber
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Phagocytic cells that digest a pathogen, then insert a bit of pathogenic antigen on their cell membrane, are described as being _____ cells.
A. natural killer B. helper T C. antigen-presenting D. memory
Biology & Microbiology