The body’s inner surfaces are protected against penetration by harmful microorganisms by ____
a. water permeable outer skin layers
b. watery mucus
c. high pH of gastric and vaginal environments
d. cilia
e. warm, moist environments
ANSWER: d
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In recombinant DNA experiments, ______ is used to cut pieces of DNA, and ______ joins these segments to form recombinant DNA
A. restriction enzyme; DNA ligase B. a transposon; a restriction enzyme C. a plasmid; DNA ligase D. DNA ligase; a restriction enzyme E. DNA ligase; a plasmid
Which of the following would be considered a carbon reservoir? Select all that apply
A. the Atlantic Ocean B. Redwood National Park C. the Great Barrier Reef D. all the organisms on Earth
When E. coli is lysed:
A. circular chromosomal DNA is released. B. circular plasmid DNA is released. C. both circular chromosomal and circular plasmid DNA are released. D. chromosomal DNA remains within the cell wall while most cellular contents are released. E. both circular chromosomal and circular plasmid DNA remain within the cell wall while most cellular contents are released.
Which hormone, made by the kidney, is necessary for red blood cell production by bone marrow?
a. erythropoietin b. hemoglobin c. insulin d. erythrocytes e. leucocytes