Which of the following must occur in order to maintain a high pressure potential within guard cells?
A. Stomata must take up more oxygen and less carbon dioxide.
B. Energy must be constantly expended.
C. Water must exit guard cells by osmosis.
D. Potassium ions must be actively transported out.
E. The rate of transpiration must increase.
Answer: B
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The alternative pathways of photosynthesis using the C4 or CAM systems are said to be compromises. Why?
A) Each one minimizes both water loss and rate of photosynthesis. B) C4 compromises on water loss and CAM compromises on photorespiration. C) Both minimize photorespiration but expend more ATP during carbon fixation. D) CAM plants allow more water loss, while C4 plants allow less CO2 into the plant. E) C4 plants allow less water loss, but CAM plants allow more water loss.
Which of the following are sensitive to streptomycin?
a. archaea b. fungi c. bacteria d. amoeba
The use of SNPs for analyzing genomes is
based on a. the nucleotide base pairing in the SNPs. b. the types of nucleotides in the SNPs. c. differences in SNPs among individuals. d. the ratio of purines to pyrimidines in SNPs. e. bonding patterns between nucleotides in the SNPs.
Which of the following statements about a resting transmembrane potential is true?
a. If the sodium-potassium pump were blocked, the transmembrane potential would become greater. b. If the resting neuron were suddenly made permeable to positive ions, a transmembrane potential would not form. c. If the resting neuron had no voltage-activated K+ channels, K+ concentrations in cytoplasm would increase. d. If the voltage-activated Na+ channels are blocked, Na+ will not enter the cytoplasm of the neuron. e. If the cytosol developed a negative charge, the resting potential would disappear..