Interesting passage. Took 11 mins , including 4 mins to read the passage . All correct .
Q25: The passage suggests which of the following about the accuracy of the commuter diatom’s biological clock?
A commuter diatom has an unusually accurate biological clock,
a consequence of the unrelenting environmental pressures to which it is subjected; any diatoms that do not burrow before the tide arrives are washed away.
C: The commuter diatom’s biological clock is likely to be more accurate than the biological clock of a species that is subject to less intense environmental pressures.
Q26: The author of the passage compares the relationship between an organism’s biological clock and its environment to the relation between a wristwatch and its owner most probably in order to Biologists have concluded that even though a diatom does not rely on the environment to keep time, environmental factors—including changes in the tide’s hydrostatic pressure, salinity, mechanical agitation, and temperature—can alter the period of its biological clock according to changes in the tidal cycle. In short, the relation between an organism’s biological clock and its environment is similar to that between a wristwatch and its owner: the owner cannot make the watch run faster or slower, but can reset the hands.
B: illustrate the way in which the period of an organism’s biological clock can be altered by environmental factors
Q27: According to the passage, the periodic behavior displayed by commuter diatoms under constant laboratory conditions is characterized by which of the following?However, when diatoms are observed under constant conditions in a laboratory, they still display periodic behavior,
continuing to burrow on schedule for several weeks.
A: Greater unpredictability than the corresponding behavior under natural conditions -- Incorrect
B: A consistent periodic schedule in the short term -- Correct
C: No difference over the long term from the corresponding behavior under natural conditions -- Not sure -- May or may not be true-- but we are told only about several weeks
D: Initial variability caused by the constant conditions of the laboratory -- Incorrect
E: Greater sensitivity to environmental factors than is the case under natural conditions -- Incorrect
28: The primary purpose of the passage is toD: examine how certain biological and environmental influences affect the tide-associated behavioral rhythms displayed by the diatom Hantzschia virgata -- Correct
According to the passage, each of the following is characteristic of the tide-associated periodic behavior of commuter diatoms EXCEPT:
Biologists have concluded that even though a diatom does not rely on the environment to keep time, environmental factors—including changes in the tide’s hydrostatic pressure, salinity, mechanical agitation, and temperature—can alter the period of its biological clock according to changes in the tidal cycle.
A. It is triggered when the diatoms are inundated by the tide -- Correct
B.It is correlated with the rise and fall of the tide -- Incorrect
C. It adjusts to changes in the tidal cycle -- Incorrect
D.It is influenced by the solar-day cycle -- However, this relation is complicated in intertidal dwellers such as commuter diatoms by the fact that these organisms are exposed to the solar-day cycle as well as to the tidal cycle, and sometimes display both solar-day and tidal periods in a single behavior.
E.It is regulated by an innate time-keeping mechanism -- This indicates that commuter diatoms, rather than relying on environmental cues to keep time, possess an internal pacemaker or biological clock that enables them to anticipate periodic changes in the environment.
Which of the following can be inferred from the passage about the effect of the solar-day cycle on the tide-associated periodic behavior displayed by commuter diatoms?
However, this relation is complicated in intertidal dwellers such as commuter diatoms by the fact that these organisms are exposed to the solar-day cycle as well as to the tidal cycle, and sometimes display both solar-day and tidal periods in a single behavior.
A The solar-day cycle makes this behavior less advantageous to the commuter diatoms at certain times of the year.
B The solar-day cycle makes this behavior somewhat more erratic.
C The solar-day cycle makes this behavior less important to the survival of the commuter diatoms.
D Because of the solar-day cycle, this behavior is forced to proceed at a more rapid pace at certain times during the 24-hour day.
E Because of the solar-day cycle, this behavior is not expressed at certain times during the 24-hour day. - Correct
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When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. - Henry Ford
The Moment You Think About Giving Up, Think Of The Reason Why You Held On So Long