What Evidence Supports the Idea That a Collision Between Two

question 16

Multiple Choice

What evidence supports the idea that a collision between two spiral galaxies might lead to the formation of a single elliptical galaxy?

• A) observations of some elliptical galaxies surrounded by shells of stars that probably formed from stars stripped out of smaller galaxies
• B) the fact that elliptical galaxies dominate the galaxy populations at the cores of dense clusters of galaxies
• C) observations of some elliptical galaxies with stars and gas clouds in their cores that orbit differently from the other stars in the galaxy
• D) observations of giant elliptical galaxies at the center of dense clusters that may have grown by consuming other galaxies
• E) all of the above

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Definitions:

Aerobic Respiration

Aerobic respiration is a biological process in which glucose is broken down using oxygen to produce energy, carbon dioxide, and water.

Pyruvate

A key intermediate in several metabolic pathways, particularly glycolysis.

Oxidative Phosphorylation

The production of ATP using energy derived from the transfer of electrons in the electron transport system of mitochondria; occurs by chemiosmosis.

Electron Transport Chain

A series of protein complexes and small organic molecules within cell membranes that transfer electrons, driving the synthesis of ATP.