The Volcano Is Currently Dormant, but in a Hypothetical Future

question 80

Multiple Choice

The volcano is currently dormant, but in a hypothetical future scenario, satellite cones at the base of Mt. Kilimanjaro spew sulphurous gases and lava, destroying all life located between the base and 1830 metres above sea level. As a result of this catastrophe, how should the frequency of the sickle-cell allele change in the remnant human population that survives above 1830 metres, and which phenomenon accounts for this change in allele frequency?

• A)decreases; disruptive selection
• B)increases; genetic drift
• C)decreases; gene flow
• D)increases; nonrandom mating
• E)decreases; bottleneck effect

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Definitions:

Input

Input refers to the data or signals that are fed into a system or device for processing or for affecting its operation.

Output

The information or signals produced by a system or device as a result of its processing or control functions.

PLC Program

A sequence of instructions written for a Programmable Logic Controller (PLC) to automate machinery or processes.

Structured Text

A high-level programming language designed for industrial automation. It resembles the syntax of Pascal and is one of the five languages for programming PLCs.