A Main-Sequence Star Is Defined as a Star

question 303

Multiple Choice

A main-sequence star is defined as a star:

• A) with a surface temperature equal to that of the Sun.
• B) in which nuclear fusion reactions generate sufficient energy to oppose further condensation of the star.
• C) whose age after birth is about 1 million years.
• D) with a luminosity precisely equal to that of the Sun.

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Definitions:

Serum Sodium Level

A measure of sodium concentration in the blood, crucial for maintaining fluid balance and neuromuscular function.

Albumin

A protein found in blood plasma that helps maintain the body's osmotic pressure and transport substances, including hormones, drugs, and nutrients.

Sodium Level

The concentration of sodium in the blood, crucial for maintaining blood pressure, fluid balance, and normal function of muscles and nerves.

Serum Potassium Level

The concentration of potassium in the blood serum, which is crucial for nerve and muscle cell function.