Centriole: Definition, Structure & Function

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Depolarization: Definition & Concept

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

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:05 What is a Centriole?
  • 1:16 Centrosome Centrioles
  • 3:07 Cilia and Flagella Centrioles
  • 4:32 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: Amanda Robb

Amanda holds a Masters in Science from Tufts Medical School in Cellular and Molecular Physiology. She has taught high school Biology and Physics for 8 years.

This lesson is about centrioles, which are an important part of cells. We will learn about what a centriole is, what it's made of, and what its role is in different cells.

What is a Centriole?

To make new humans, we have to get a sperm and an egg together. But how does that sperm find its way to the egg? It has to swim quite far using a flagellum. Once it's at the egg, they have to start dividing millions of times to make a new human. How does this miracle of life happen? Surprisingly, the answer is centrioles.

First, to understand what a centriole is and what it does, we need to understand the parts of a cell. Cells are the basic building blocks of life. All living things are made of cells. Within cells, there are tiny working parts called organelles. Organelles each have a different job in the cell. A centriole is an organelle that helps cells divide, or make copies of themselves.

Centrioles are only found in animal cells. All centrioles are made of protein strands called microtubules. Centrioles are made of nine triplets of microtubules arranged in a cylinder. Think of each microtubule like a plastic PVC pipe. The pipes are arranged with three put together in a triplet, then nine of those triplets are glued together to form an even bigger pipe. When two centrioles come together, they usually make a right angle.

Centrosome Centrioles

Centrioles help form three important structures for cells: the centrosome, cilia, and flagella. Let's start with centrosome centrioles. These words sound pretty similar, huh? To really understand the difference, we need to understand cell division, or mitosis. Mitosis is a process where cells divide and make two new, identical cells. Before mitosis can start, the cells need to make two copies of their DNA. Each one will go to a new cell, so that the new cells have the exact, correct amount of DNA.

The centrosome and centrioles are crucial for this process. During cell division, two centrioles come together with some other special proteins and form the centrosome. This is an image of a centrosome, made of two centrioles and microtubules.

Centrosomes are made of two centrioles and microtubules

Let's think of an analogy to keep these two vocabulary words straight before we move on. The centrosome can be thought of like a shipping box being delivered to your door. The shipping box is like the centrosome. Inside the box are two presents, the centrioles. Each present, or centriole, is wrapped separately. But, the shipping box is important too. It's made of its own cardboard and tape and brings the presents together, safely, to your house where you can enjoy them. The centrosome encases the centrioles with some extra proteins, just like the shipping box encases your presents.

Now, during cell division, there are two centrosomes, each with two centrioles. Here's what happens:

  1. The centrosomes move to opposite ends of the cell where they make even more microtubules.
  2. The microtubules grow towards the center of the cell and attach to the duplicated DNA.
  3. The centrosomes pull the DNA copies apart, giving each new cell just the right amount of DNA.

Cilia and Flagella Centrioles

Centrioles are also used in the cell structures' cilia and flagella. Cilia are lots of small projections on cells, like little hairs that whip back and forth to move the cell or to move material over or around the cell. Cells in the lungs, for example, use cilia to move mucus out of the lungs.

To unlock this lesson you must be a 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

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
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? 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