The Main Sequence Has a Limit at the Lower End

question 14

Multiple Choice

The main sequence has a limit at the lower end because

• A) low mass stars form from the interstellar medium very rarely.
• B) low mass objects are composed primarily of solids, not gases.
• C) pressure does not depend on temperature in degenerate matter.
• D) the lower limit represents when the radius of the star would be zero.
• E) there is a minimum temperature for hydrogen nuclear fusion (the definition of a star).

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Definitions:

Huntington Disease

A genetic neurodegenerative disorder characterized by the progressive breakdown of nerve cells in the brain, leading to physical and cognitive decline.

Hyperkinetic Symptoms

Manifestations characterized by excessive or abnormal involuntary movements, often found in disorders like Tourette's syndrome or Huntington's disease.

Dopamine Cells

Neurons that produce and release dopamine, a neurotransmitter involved in reward, motivation, and motor control.

Motor Cortex

The part of the cerebral cortex that plays a role in planning, controlling, and carrying out voluntary movements.