Which Motor Symptom, Visible in the Hands, Is Characteristic of Parkinson's

question 3

Multiple Choice

Which motor symptom, visible in the hands, is characteristic of Parkinson's disease?

• A) blue discolor
• B) red discolor
• C) tremor
• D) severe edema
• E) swollen joints

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Definitions:

Mechanical Isolation

an evolutionary mechanism that prevents species from interbreeding due to physical differences in reproductive structures.

Hybrid Inviability

A condition where hybrid offspring fail to develop or reach sexual maturity, reducing gene flow between different species or populations.

Hybrid Sterility

A condition where offspring from the cross between two different species are infertile, preventing them from producing offspring.

Postzygotic Barrier

One of several reproductive isolating mechanisms that prevent gene flow between species after fertilization has taken place (e.g., hybrid inviability, hybrid sterility, and hybrid breakdown). Compare with prezygotic barrier.