1.2: The Cell Membrane — Read

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The cell membrane, also called the plasma membrane or plasmalemma, is a barrier between the cell's internal contents and the surrounding external environment, comprising interstitial fluid or tissue fluid. In addition to its protective function, the cell membrane regulates the passage of substances across its surface; hence, it is called semipermeable or selectively permeable. Membrane permeability determines how induction agents cross the blood-brain barrier and how local anesthetic agents diffuse across the cell membrane.

1.2.1: Structure and Composition of Cell Membrane
This page describes the cell membrane's structure, which is 5-10 nm thick and primarily made of lipids, proteins, and carbohydrates. Phospholipids are the main lipids, with cholesterol aiding fluidity. Various proteins assist in transport, while carbohydrates form glycolipids and glycoproteins on the surface. The fluid mosaic model highlights the membrane's dynamic nature, emphasizing motion over rigidity.
- 1.2.1.1: Membrane Lipids
- 1.2.1.2: Membrane Proteins

This page titled 1.2: The Cell Membrane was last modified on Tue, 18 Aug 2026 18:26:44 GMT and is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Chaya Gopalan (Consortium of Academic and Research Libraries in Illinois (CARLI)) .

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