If You Found a Galaxy with an H $\alpha$ Emission Line That Had a Wavelength of 756

question 38

Multiple Choice

If you found a galaxy with an H $\alpha$ emission line that had a wavelength of 756.3 nm,what would be the galaxy's distance if the Hubble constant is 22 km/s/Mly? Note that the rest wavelength of the H $\alpha$ emission line is 656.3 nm.

• A) 1,120 km/s
• B) 2,080 km/s
• C) 6,070 km/s
• D) 8,500 km/s

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Definitions:

Epigenetic Mechanisms

Biological processes that alter gene expression without changing the DNA sequence, influencing organism development and behavior.

Gene Expression

Gene expression is the process by which information from a gene is used to synthesize a functional gene product, often a protein, which can affect the characteristics of a cell or an organism.

Histone Modification

Chemical modifications to the histone proteins around which DNA is wrapped, influencing gene expression without altering the DNA sequence itself.

Ependymal Cells

Glial cells lining the ventricles of the brain and the central canal of the spinal cord, involved in the production and circulation of cerebrospinal fluid.