Download presentation
Presentation is loading. Please wait.
1
Cell Membrane Objectives
Summarize the main functions of a cell membrane. List and illustrate the main structures of a cell membrane, in terms of phospholipids, proteins and carbohydrates. Compare and contrast cell membranes to cell walls.
2
Cell Membrane A cell membrane has 3 main functions Functions
Controls what enters / exits cell. Protects cell. Supports cells. Cell membrane surrounds cell.
3
Cell Membrane A cell membrane is made of 3 types of organic molecules
Structure Phospholipid bilayer Proteins (integral and peripheral) Carbohydrates
4
Cell Membrane Phospholipid bilayer
Most of a cell membrane is made of a phospholipid bilayer Double layer of phospholipid molecules. Fluid and flexible. Allows some small, non-polar molecules through, but blocks large or charged molecules.
5
Cell Membrane Phospholipid molecules have a “head” and a “tail”
Phospholipid molecules arrange themselves into bilayer because of their special structure. H O Hydrophilic head “loves” water. Hydrophobic tail “fears” water.
6
Cell Membrane Integral and peripheral proteins
Proteins are attached to phospholipid bilayer and perform many functions: Integral proteins are attached to membrane. They can transport materials or carry signals in and out of the cell. Peripheral proteins temporarily attach to phospholipid bilayer or integral proteins.
7
Cell Membrane Carbohydrates
Some carbohydrate chains are attached to the membrane surface. These help cells identify and recognize each other.
8
Cell Membrane Cell Wall
A cell wall is a hard, flexible extra layer surrounding the cell membrane in some organisms, including: Plants Fungi Some bacteria
9
Exit Ticket 1. Summarize the main functions of a cell membrane.
The main functions of a cell membrane include… 2. List and illustrate the main structures of a cell membrane, in terms of phospholipids, proteins and carbohydrates. The main structures of a cell membrane includes… Illustration of cell membrane: … 3. Compare and contrast cell membranes to cell walls. In comparison, a cell membrane and cell wall both _______________________. In contrast, a cell membrane is _____________________________________________, while a cell wall is ___________________________________________________________.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.