A Low-Mass Main-Sequence Star's Climb Up the Red Giant Branch

question 47

Multiple Choice

A low-mass main-sequence star's climb up the red giant branch is halted by

• A) the end of hydrogen shell burning.
• B) the beginning of helium fusion in the core.
• C) electron-degeneracy pressure in the core.
• D) instabilities in the star's expanding outer layers.
• E) an explosion that destroys the star.

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Definitions:

Bilirubin

Bile pigment derived from hemoglobin during the destruction of red blood cells.

Erythrocytes

Oxygen-carrying blood cells, also known as red blood cells, which are responsible for delivering oxygen from the lungs to all parts of the body.

Hemoglobin

An iron-containing protein in red blood cells that transports oxygen from the lungs to the tissues of the body.

Platelets

Small blood cells essential for blood clotting, helping to stop bleeding by clumping together and forming plugs in blood vessel injuries.