Which of the following organisms first introduced oxygen into Earth's atmosphere?
A) cyanobacteria
B) methanogens
C) early protozoans
D) plants
E) green algae
Ans: A) cyanobacteria
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Researchers once believed that mammals were born with all of the neurons they would ever have. Recent research has proven this to be untrue. Approximately how many new neurons develop in the mammalian hippocampus daily?
a. 10 b. 100 c. 1,000 d. 10,000
Which of the following countries has the most
extensive family-planning program? a. United States b. Brazil c. China d. Japan e. Pakistan
A Gram-positive psychrotrophic rod ________ is a frequent contaminant of dairy products and meat and survives phagocytosis
A) Escherichia coli B) Mycobacterium leprae C) Clostridium perfringens D) Bacillus thuringiensis E) Listeria monocytogenes
Finding ________ in water is a good indication that it has been fecally contaminated.
Fill in the blank(s) with the appropriate word(s).