plasma membrane- bio test

Phospholipids Have a hydrophilic (water-loving) head and hydrophobic (water-fearing) tails. In water, they arrange into a bilayer.\

Phospholipid Bilayer The heads face outward toward the watery environments inside and outside the cell, while the tails face inward away from water, forming a hydrophobic core.\

Role of the Bilayer Acts as a barrier separating the cell’s interior from its surroundings.\

Fluid Mosaic Model A model describing the plasma membrane as a flexible, dynamic structure made of different components.\

Why is the membrane called "fluid"? Phospholipids and proteins can move laterally within the membrane, making it flexible and dynamic.\

Why is the membrane called "mosaic"? The membrane contains different components, including phospholipids, proteins, cholesterol, and carbohydrates, scattered throughout the bilayer.\

What molecules pass most easily through the membrane? Small, nonpolar (hydrophobic), and uncharged molecules.\

3 Factors That Influence Permeability Temperature, lipid composition, and molecule size and polarity.\

Membrane Properties — Barrier Separates the cell’s interior from its surroundings.\

Membrane Properties — Communication Allows cells to receive and send signals.\

Membrane Properties — Structure Provides structural support for the cell.\

Membrane Properties — Protection Helps protect the cell and its contents.\

Membrane Properties — Compartmentalization Separates the cell’s internal environment from the external environment.\

What does the membrane do? Regulates what enters and exits the cell through selective permeability.\

Selective Permeability The ability of the membrane to control which substances enter and leave the cell.\

How does the membrane help maintain homeostasis? It regulates the movement of substances into and out of the cell, helping maintain stable internal conditions.\

How does the membrane facilitate communication? Membrane proteins allow cells to receive and respond to signals.\

How does the membrane provide structural support and protection? The membrane helps maintain cell structure and protects the cell’s contents.\

How does the membrane allow cell recognition? Carbohydrates attached to membrane proteins and lipids act as identification markers.\

What is the plasma membrane made of? Phospholipids, proteins, cholesterol, and carbohydrates.\

What are the main components of the plasma membrane? Phospholipids, proteins, cholesterol, and carbohydrates.\

Hydrophilic "Water-loving"; attracted to and interacts with water.\

Hydrophobic "Water-fearing"; avoids water and tends to interact with nonpolar substances.\

Hydrophobic Core The inner portion of the phospholipid bilayer formed by the hydrophobic tails.\

Why do phospholipids form a bilayer in water? The hydrophilic heads interact with water while the hydrophobic tails avoid water, causing the phospholipids to arrange into a bilayer.