One of the Discoveries Which Led to the Modern View

question 14

Multiple Choice

One of the discoveries which led to the modern view of the solar system was that the orbits of the planets are ________.

• A)circles
• B)ellipses
• C)hyperbolas
• D)parabolas

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Definitions:

Calmodulin

Protein receptor for Ca2+ that plays a role in many Ca2+-regulated processes, such as smooth muscle contraction.

Steroid Hormones

Lipid-soluble molecules derived from cholesterol that regulate a variety of physiological functions including metabolism, inflammation, and sexual function.

Plasma Membrane

The lipid bilayer that surrounds a cell, controlling the passage of substances in and out of the cell.

Phosphodiesterase

Enzyme that splits phosphodiester bonds—that is, that breaks down cyclic AMP to AMP.