Definition

Noun: A thin, semi-permeable biological structure that surrounds the cytoplasm of a cell. It is primarily composed of a double layer of lipids (phospholipids) and embedded proteins. Its primary functions are to define the cell's boundary, protect its interior, and regulate the passage of ions (such as sodium, potassium, or calcium) and other molecules into and out of the cell.

Usage Examples

• Noun:
  • The cell membrane acts as a selective barrier.
  • Nutrients must pass through the cell membrane to enter the cell.
  • Damage to the cell membrane can cause the cell to die.

Advanced Usage

• "Fluid mosaic model": This is the scientific model describing the structure of the cell membrane, emphasizing that it is fluid (components can move) and a mosaic (made of different types of molecules like lipids and proteins).
• "Membrane potential": This refers to the electrical charge difference across the cell membrane, crucial for nerve and muscle cell function.
• "Plasma membrane": This is a synonym for cell membrane, often used interchangeably in biology.

Variants and Related Words

• Plasma membrane (n): A direct synonym for cell membrane.
• Cytoplasmic membrane (n): Another term for the cell membrane, emphasizing its location around the cytoplasm.
• Phospholipid bilayer (n): The fundamental double-layered lipid structure that forms the core framework of the cell membrane.
• Semi-permeable (adj): Describes the key property of the cell membrane, allowing only certain substances to pass through.

Synonyms

• Plasma membrane
• Cytoplasmic membrane
• Plasmalemma (a more technical term)

Related Phrases / Concepts

• "Cross the membrane": To move from one side of the cell membrane to the other.
  • Oxygen molecules can easily cross the membrane.
• "Embedded in the membrane": Describes proteins or other molecules that are integrated into the structure of the cell membrane.
  • Receptor proteins are embedded in the membrane.
• "Membrane integrity": Refers to the wholeness and proper function of the cell membrane.
  • The chemical compromised the membrane integrity.

Noun

1. a thin membrane (a double layer of lipids) enclosing the cytoplasm of a cell; proteins in the membrane control passage of ions (like sodium or potassium or calcium) in and out of the cell
   • all cells have a cell membrane