Anchorage Dependence: Definition & Overview

Instructor: Stephanie Gorski

Steph has a PhD in Entomology and teaches college biology and ecology.

In this lesson, we will look at what anchorage dependence means. We will also see why anchorage dependence is important in cells, how cells 'know' if they are anchored to a surface, and what happens if cells become anchorage independent.

Anchorage Dependence Defined

You probably feel better about your life when you feel grounded. When you are connected to your friends, family and community and to your body through physical activity, you are better able to face the challenges in your life. What if I told you that your cells need to be grounded, too? And it's a good thing they do!

Anchorage dependent cells need to be 'grounded' to divide. That is, if they aren't anchored to a surface - such as a tissue in your body or a jar in a laboratory - they won't reproduce. Cells that aren't anchored may even undergo apoptosis, which is basically programmed cell death.

In this lesson, we are going to learn what happens when cells aren't grounded, and how cells 'know' whether or not they're grounded. Then, we'll talk about what happens when cells break the rules and divide even when they shouldn't.


Why would cells be programmed to kill themselves? Apoptosis is actually a very important feature that allows your cells to work together as a team. In single-celled organisms, every cell is out for itself. But in multicellular organisms, cells have to work together for the good of the body.

Sometimes, what's good for your body is getting rid of unnecessary cells. For instance, a cell that is damaged or has been infected by a virus may undergo apoptosis so that the damage won't spread, or cells may be needed in an earlier stage of development but no longer be necessary as you get older. For instance, when you were a developing fetus, you grew a whole bunch of neurons you didn't need. Most of these neurons died off as you were forming the neural pathways you now use to think. Another classic example of apoptosis in development is the tail of a tadpole. Tadpoles need tails, but adult frogs are better off without them. So apoptosis is used during the transition from tadpole to frog so that adult frogs do not have tails.

Apoptosis helps this tadpole become a frog.
Apoptosis helps this tadpole become a frog.

How Cells Know What to Do

So, how do cells know what to do? Integrins are proteins that can help regulate whether our cell undergoes apoptosis, will grow and divide, or will simply survive intact. Not coincidentally, integrins are also the proteins that cells use to stick to a surface.


How do cells 'know' if they are stuck to a surface or not? Well, free-floating cells often have a very large, folded, wrinkled cell surface. Think of a raisin, but with even deeper wrinkles. Attached to this surface are growth factor receptors. Growth factors are signals that your body produces to let cells know that it is a good time to divide. Growth factor receptors are like little antennae that stick on the surface of the cell and pick up growth factors when they are present.

When a cell is free-floating, all those raisin-like folds seem to cover up the growth factor receptors, so even if growth factor is present, the receptors may not detect it. On the other hand, when a cell is attached to a surface, it becomes stretched out. More growth factor receptors are exposed to the surrounding environment, and so, the cell is better able to tune into signals that tell it to divide.

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 now
Create an account to start this course today
Used by over 30 million students worldwide
Create an account