What causes a decrease in oxygen levels beyond the sunlit layer?
a. The respiration from marine animals and bacteria
b. The by-products of photosynthesis
c. There are fewer animals present
d. Decreased saturation because of cooler water
ANS: A
The high level of oxygen at the surface is the by-products of photosynthesis. Beyond that layer, the
oxygen decreases due to the respiration of marine animals. At deep depths, oxygen levels increase
slightly because there are fewer animals at those depths. Information can be found in the section Gases
Dissolve in Seawater.
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a. True b. False Indicate whether the statement is true or false
Which pairing is most accurate?
A) microscale-chinook wind B) synoptic scale-sea breeze C) mesoscale-land breeze D) planetary scale-lake breeze
A coastline of emergence would most likely result from:
a. rising sea level. b. subsiding land. c. a tsunami. d. tectonic uplift of land in the coastal zone. e. a barrier island.
Which of the following is true of class I and class II MHC molecules?
A) They both are transmembrane proteins B) They both have peptide binding variable domains C) both a and b D) neither a nor b