How Is Galactic Evolution Described by the Hubble Tuning Fork

question 238

Multiple Choice

How is galactic evolution described by the Hubble tuning fork diagram?

• A) Galaxies begin as type E0 and evolve to lenticular and then continue as either normal or barred spirals.
• B) Galaxies are created as either normal or barred spirals, but either eventually evolves to lenticular. These then evolve through the various types of ellipticals.
• C) Everything starts as a lenticular galaxy. Then, for reasons not well understood, the subsequent evolution is either as a spiral (normal or barred) or as an elliptical.
• D) We do not believe galactic evolution is described by the Hubble tuning fork diagram.

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Definitions:

Parental Strands

Refers to the original strands of DNA or RNA from which new strands are synthesized during replication.

Conservative Replication

A hypothetical model of DNA replication where the original DNA molecule is fully preserved and a completely new copy is produced.

Mismatch Repair Enzymes

A system within cells that repairs mispaired nucleotides which may arise during DNA replication and recombination, as well as repairing some forms of DNA damage.

DNA Polymerase

A catalyst that constructs DNA strands using deoxyribonucleotides as the foundational components of DNA.