The Concentrations of Ions Are Very Different Inside and Outside

question 16

Multiple Choice

The concentrations of ions are very different inside and outside a nerve cell due to ________.

• A) osmosis
• B) diffusion
• C) sodium-potassium pumps
• D) symports and antiports

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Definitions:

Lower Mantle

The lower mantle is the region of the Earth's interior between the core-mantle boundary and the upper mantle, characterized by high temperatures and pressures, composed mostly of silicate minerals.

Outer Core

The molten outer part of Earth’s core, extending from a depth of 2,900 km to 5,100 km.

Inner Core

The solid central part of Earth’s core, extending from a depth of about 5,100 kilometers to the center of Earth (6,371 kilometers); its radius is about one-third of the whole core.

Contaminated Groundwater

Water below the Earth's surface that has been polluted by chemical substances, biological organisms, or other contaminants, affecting its safety and usability.