A Star Is Observed to Have Extremely Strong Lines of Hydrogen,very

question 13

Multiple Choice

A star is observed to have extremely strong lines of hydrogen,very weak neutral helium,and weak neutral metals.The spectral type of such a star is closest to

• A)O5
• B)B2
• C)A0
• D)K5
• E)M8

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Definitions:

Cytosine Dimers

Incorrect pairing of cytosine bases that can occur due to damage, often caused by ultraviolet radiation, leading to mutations.

Purine Base

A type of nitrogenous base found in DNA and RNA, including adenine and guanine, which are essential for genetic information.

Pyrimidine Base

A nitrogenous base that is one of the components of nucleic acids, including cytosine, thymine (in DNA), and uracil (in RNA).

Two Rings

Refers to the molecular structure characteristic of certain organic compounds, notably purines and certain types of aromatic hydrocarbons, consisting of two connected rings of atoms.