Down Syndrome Results from Trisomy of Chromosome 21

question 64

Multiple Choice

Down syndrome results from trisomy of chromosome 21.Which of the following is NOT an example of how this may have happened?

• A) translocation of chromosome 21
• B) failure of the homologous pair for chromosome 21 to separate in meiosis I
• C) inversion of a portion of chromosome 21 during S phase
• D) failure of the sister chromatids in a duplicated chromosome 21 to separate in meiosis II

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Definitions:

Operant Conditioning

A learning process through which the strength of a behavior is modified by reinforcement or punishment, introduced by B.F. Skinner.

Unconditioned Response

A naturally occurring response to an unconditioned stimulus, such as salivating when smelling food.

Fixed-ratio Schedule

A schedule of reinforcement where a response is reinforced only after a specified number of responses, leading to a rapid response rate followed by a short pause.

Industrial Psychologist

A professional who applies psychological theories and principles to understand human behavior in workplaces, aiming to improve employee well-being and organizational efficiency.