What Is the Function of Cholesterol in the Cell Membrane?

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: What Is the Function of the Nucleus in Eukaryotic Cells?

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:02 Cholesterol in the…
  • 1:18 Structure of the Cell Membrane
  • 2:40 Role of Cholesterol
  • 4:35 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Emily Lockhart

Emily has taught science and has a master's degree in education.

This lesson looks at the details of the cell membrane. It focuses on the structure of the membrane and cholesterol's role in maintaining a healthy, strong cell membrane.

Cholesterol in the Cell Membrane

When you sleep in a cold room, you might have a couple of layers of blankets that you roll up in to keep warm. The blankets help protect your body from the cold; this is similar to the role the cell membrane plays when it 'rolls up' around a cell. Your body is made up of trillions of cells, which are small units working together to create organisms - like you! If you travel inside the cell, you'll find it's filled with fluid called plasma and many small parts that are vulnerable to the outside world. The cell membrane, also called the plasma membrane, surrounds the cell and protects what is inside from the outside environment. This lesson looks at the cell membrane in detail and focuses on cholesterol, which is one of the components found in the cell membrane.

The cell membrane is described as a fluid mosaic. This is because the structure of the membrane is flexible and fluid, and also made up of a variety of molecules. Four main molecules make up the mosaic structure of the cell membrane. They are phospholipids, cholesterol, proteins, and carbohydrates. Each of these molecules gives the cell membrane unique characteristics due to the way the molecules interact with each other. To understand cholesterol's role in the membrane, let's look at the basic structure of a cell membrane.

Structure of the Cell Membrane

Phospholipids are the molecules that make up most of the membrane structure. A single phospholipid molecule has two parts, a head that is attracted to water and a tail that is repelled by water. The head is referred to as hydrophilic, or water-loving, while the tail is called hydrophobic, or water-hating. Both the outside and inside of a cell are aqueous. This causes the phospholipids to orient themselves into layers when in water solutions, just like vegetable oil does when mixed with water.

This aqueous environment causes two phospholipids to stack together like magnets. They attract tail to tail with the heads facing outwards. Then these two molecule structures join side-by-side with two other molecular structures. This creates a two-layer membrane that surrounds the cell. The cell is just like you sleeping rolled up in a quilt and sheet. The outside ''blanket'' of the membrane has heads pointed out and tails facing in. The inside ''blanket'' has heads pointing towards the plasma and tails facing in. The tails that face in bond weakly to each other. The bond is similar to the static of your sheets, allowing for a temporary bond to the quilt. These two layers don't lock together but instead, end up sliding past one another like the quilt and the sheet. It's important to the vitality of the cell that the membrane layers remain fluid.

To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account