The following question is based on the observation that several dozen different proteins comprise the prokaryotic flagellum and its attachment to the prokaryotic cell, producing a highly complex structure.
If the complex protein assemblage of the prokaryotic flagellum arose by the same general processes as those of the complex eyes of molluscs (such as squids and octopi), then
A) natural selection cannot account for the rise of the prokaryotic flagellum.B) ancestral versions of this protein assemblage were either less functional or had different functions than modern prokaryotic flagella.
C) scientists should accept the conclusion that neither eyes nor flagella could have arisen by evolution.
D) we can conclude that both of these structures must have arisen through the direct action of an "intelligent designer."
Answer: B
Certain proteins of the complex motor that drives bacterial flagella are modified versions of proteins that had previously belonged to plasma membrane pumps. This evidence supports the claim that
A) some structures are so complex that natural selection cannot, and will not, explain their origins.B) the power of natural selection allows it to act in an almost predictive fashion, producing organs that will be needed in future environments.
C) the motors of bacterial flagella were originally synthesized abiotically.
D) natural selection can produce new structures by coupling together parts of other structures.
E) bacteria that possess flagella must have lost the ability to pump certain chemicals across their plasma membranes.
Answer: D
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