Based on the Number of Galaxies Visible in the Hubble

question 2

Multiple Choice

Based on the number of galaxies visible in the Hubble Deep Field (Figure 16.1 in your textbook) , the estimated number of galaxies in our observable universe is about .

• A)Infinity
• B)100 million
• C)50,000
• D)100 billion

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Definitions:

Cyclic Pathway

A series of biochemical reactions that occur in a sequence where the last step regenerates a reactant for the first step, forming a cycle, such as in the citric acid cycle.

Fossil Fuels

Natural fuels formed from the remains of ancient organisms, such as coal, oil, and natural gas, used as a source of energy.

Photosynthetic Organisms

Organisms that convert light energy into chemical energy through photosynthesis, using water and carbon dioxide to produce oxygen and glucose.

Chlorophyll A

Main photosynthetic pigment in plants.