The Pentose Phosphate Pathway

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Substrate-level Phosphorylation and Oxidative Phosphorylation

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

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:00 The Pentose Phosphate Pathway
  • 1:00 The PPP and Glycolysis
  • 1:50 The Oxidation Phase
  • 2:34 The Isomerization Phase
  • 3:20 The Rearrangement Phase
  • 4:02 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: Christopher Muscato

Chris has a master's degree in history and teaches at the University of Northern Colorado.

There are hundreds of various chemical reactions that occur within cells. In this lesson, we are going to check out one of those reactions, called the pentose phosphate pathway. Let's see what this reaction is, as well as what it produces and why it's important.

The Pentose Phosphate Pathway

Growing up, we are often told not to take shortcuts. It seems like good advice, the only problem is that nature likes shortcuts. Even within our own bodies, nature creates various chemical reactions within cells called metabolic pathways that create or break down various molecules needed for cellular growth. One big one is the pentose phosphate pathway, a metabolic pathway for the creation of the molecule NADPH. We'll talk more about what this is in a bit, but for now, just trust me that it's important. The pentose phosphate pathway is the main way that cells create NADPH, as well as other important molecules like sugars with 5-carbons called pentoses (after which the pathway is named). These molecules are all very important for our cells, so it's lucky that nature has some great shortcuts to get there.

The PPP and Glycolysis

If we're going to take a stroll along the pentose phosphate pathway, we've got to start with the process of glycolysis, a metabolic process that breaks up glucose molecules into smaller nutrients. This is called a catabolic process, which means it breaks large molecules into smaller parts. The opposite is an anabolic process, in which molecules are built from smaller units. The pentose phosphate pathway is going to involve the creation of a molecule, and that means it needs things to build with. That's why we're starting with glycolysis. This catabolic process breaks apart larger glucose molecules, and one of the products is the smaller molecule glucose-6-P. With this, the pentose phosphate pathway can get underway.

The Oxidation Phase

There are three phases to the pentose phosphate pathway, each of which has a different purpose. The first is the oxidation phase, in which glucose-6-P is oxidized. Now, we could go into the minutia of this process, but the end result is the creation of the molecule NADPH, which is one of the primary molecules responsible for anabolic processes. A large number of anabolic processes that involve building up tissues in the cells require this molecule, so it's pretty important. In fact, the pentose phosphate pathway is one of the main ways that the NADPH molecule is synthesized within a cell.

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