The Tilt Angle of Earth's Spin Axis to the Direction

question 219

Multiple Choice

The tilt angle of Earth's spin axis to the direction perpendicular to the ecliptic (known as the ecliptic pole)

• A) is 90° and fixed.
• B) varies rapidly through the year from +23.5° to -23.5°.
• C) is 23.5° and fixed.
• D) is 0° and fixed because this defines the ecliptic plane.

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Definitions:

Oxidation Reactions

Chemical reactions that involve the transfer of electrons, resulting in an increase in oxidation state, often associated with the release of energy.

Catabolism

Catabolism refers to the set of metabolic pathways that break down molecules into smaller units, releasing energy stored within chemical bonds.

Anabolism

The constructive phase of metabolism in which the body cells synthesize complex molecules from simpler ones for growth, repair, and storage.

Substrate

A surface or material on or from which an organism lives, grows, or obtains its nourishment; in biochemistry, it's the substance on which an enzyme acts.