​Horseshoe Crabs Have Lived in the Earth's Oceans for ____

question 68

Multiple Choice

​Horseshoe crabs have lived in the earth's oceans for ____ years.

• A) ​about 4 thousand
• B) ​close to 400 thousand
• C) ​less than 40 million
• D) ​over 400 million
• E) ​over 4 billion

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Definitions:

Plasma Membrane

The lipid bilayer that forms the outer boundary of a cell, regulating the passage of substances in and out of the cell.

Phospholipids

Phospholipids are a class of lipids that are a major component of all cell membranes as they can form lipid bilayers.

Voltage-Gated Channels

Protein channels in cell membranes that open or close in response to changes in membrane potential, crucial for nerve impulse transmission.

Receptor Proteins

Proteins on the surface of cells that bind to specific molecules, initiating a biological response.