Precession of Earth's Axis of Rotation Is Caused By

question 40

Multiple Choice

Precession of Earth's axis of rotation is caused by:

• A) changes in the shape of Earth's orbit due to the gravitational pull of the Moon.
• B) the gravitational pull of the Moon and the Sun on Earth's equatorial bulge.
• C) changes in Earth's rate of rotation (length of the day) caused primarily by the gravitational pull of the Moon.
• D) the friction between the tides and the ocean floor.

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Definitions:

SA Node

The sinoatrial node is a collection of cells located in the heart's right atrium, responsible for determining the heart's rhythm by creating electrical signals.

AV Node

The atrioventricular node, a part of the electrical conduction system of the heart that coordinates the top of the heart. It plays a crucial role in the control of the heart rate.

Purkinje Fibers

Purkinje fibers are specialized cardiac muscle fibers that conduct electrical impulses in the heart, contributing to the regulation of heartbeats.

Resting Membrane Potential

The voltage difference across a cell's plasma membrane in the absence of stimulation, crucial for the transmission of nerve impulses.