Which of the following statements is true regarding atmospheric CO2 levels during the last 400,000 years?
A. Atmospheric CO2 levels have remained
relatively constant, and have only increased
since the 1800s.
B. Atmospheric CO2 levels fluctuate
periodically, with the highest levels occurring
during interglacial periods.
C. Atmospheric CO2 levels fluctuate
periodically, with the highest levels occurring
during glacial periods.
D. Correlation exists between low levels of
atmospheric CO2 and high temperatures.
E. Causation exists between low levels of
atmospheric CO2 and high temperatures.
B
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Which of the following inaccurately represents normal forces across capillary walls?
A) Interstitial fluid oncotic pressure is almost zero. B) At rest, net filtration occurs across capillary walls. C) Interstitial fluid hydrostatic pressure increases from arteriole end to venous end. D) Capillary hydrostatic pressure decreases from arteriole end to venous end. E) Capillary oncotic pressure is due primarily to plasma proteins.
Which of the following is a plausible reason for why it may be difficult to treat infections that arise from tooth decay?
A) Biofilm bacteria that cause tooth decay begin to produce endospores as a means to deter effects of antibiotics. B) Binary fission in biofilm bacteria that cause tooth decay begins to decrease as the biofilm community becomes more complex, thereby producing fewer bacterial cells for antibiotics to penetrate. C) As the biofilm that causes tooth decay becomes larger, its structure makes it difficult for antibiotics to break through bacterial cell walls. D) Bacteria of the biofilm that cause tooth decay form a symbiotic relationship with the antibiotics and therefore diminish antibiotic effectiveness.
Which of the following is not a typical attribute of an early-successional species?
A) rapid growth B) excellent dispersal ability C) large seed size D) shade-intolerance E) ability to colonize unexploited environments
What are the functions of each of the four biological macromolecules?
What will be an ideal response?