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Apuntes

• Subtopic: Components of a Membrane A cell membrane is primarily composed of a phospholipid bilayer, along with proteins, carbohydrates, glycolipids, glycoproteins, and cholesterol. The phospholipid bilayer is amphipathic, meaning it has both hydrophilic (water-loving) and hydrophobic (water-fearing) regions. The hydrophilic heads face the water, while the hydrophobic tails are oriented away from it. This structure allows the membrane to be fluid, which is crucial for its proper function. • Subtopic: Importance of Membrane Fluidity Membrane fluidity is essential because it affects the membrane's permeability and functionality. The fluid mosaic model describes the membrane as a dynamic structure where lipids and proteins can move sideways within their layer. Cholesterol acts as a fluidity buffer, helping the membrane resist changes in fluidity due to temperature fluctuations. Evolution has enabled organisms to maintain membrane fluidity even in extreme conditions. • Subtopic: Types of Proteins in the Membrane Proteins embedded in the membrane determine most of its functions. There are several types of proteins: - Integral proteins penetrate the hydrophobic interior of the lip...