The Molecular Clock Used to Date the Emergence of the 2009

question 17

Multiple Choice

The molecular clock used to date the emergence of the 2009 H1N1 strain would be inaccurate if

• A) mutations arose at different rates in different lineages.
• B) the most recent common ancestor of the viral strains existed long ago.
• C) the most recent common ancestor of the viral strains existed recently.
• D) None of the given choices are correct.

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Definitions:

Lymphocyte

A type of white blood cell that is part of the immune system, helping the body to fight infection and disease.

Neutrophil

A type of white blood cell important in defending the body against infection and disease.

Blood Smear

A laboratory test procedure that involves spreading a thin layer of blood on a microscope slide for the purpose of examining blood cells under a microscope.

Eosinophils

A type of white blood cell that plays a key role in the body's immune response, especially in combating parasitic infections and in allergic reactions.