Anaphase: Definition & Concept Video

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Karyotype: Definition, Disorders & Analysis

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

Take Quiz Watch Next Lesson
 Replay
Your next lesson will play in 10 seconds
  • 0:00 What Is Anaphase?
  • 2:06 What Happens During Anaphase?
  • 2:58 What If Something Goes Wrong?
  • 5:08 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

Timeline
Autoplay
Autoplay
Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Angela Lynn Swafford

Lynn has a BS and MS in biology and has taught many college biology courses.

Anaphase is a very important stage of cell division. In this lesson, you can lean about the process of anaphase and what happens if something goes wrong during it.

What Is Anaphase?

Most eukaryotic cells, or those cells that have a nucleus, undergo a process called mitosis when they need to reproduce. Mitosis is the division of the nucleus. The nucleus is the structure that contains DNA, which holds genetic information.

DNA can be arranged loosely as chromatin, or it can be condensed into chromosomes. Chromosomes only become visible during mitosis. When a cell is not dividing, it is in a stage called interphase, in which chromatin is present.

To get ready for mitosis, a cell must first undergo DNA replication during interphase. This process duplicates every strand of DNA so that there are two copies of every chromosome. The two copies are called sister chromatids and are attached at the centromere. During mitosis, kinetochores will develop on the outer sides of each centromere region. Kinetochores are the attachment points for spindle fibers. Spindle fibers extend from centrioles to kinetochores and are responsible for moving chromosomes around during mitosis.

Once DNA replication is complete, nuclear division proceeds in four stages:

  1. Prophase: chromosomes become visible, nuclear envelope disappears, kinetochores and spindle fibers form
  2. Metaphase: chromosomes align in the center of the cell at the metaphase plate
  3. Anaphase: chromosomes move outwards, towards opposite poles of the cell
  4. Telophase: reverse of prophase

Once the nucleus is divided in two, the entire cell can split into two new cells in a process called cytokinesis. In cytokinesis, a cleavage furrow, or pinched-in area, forms where the metaphase plate was and splits the cell into two.

What Happens During Anaphase?

Let's take a closer look at what happens during anaphase of mitosis. Each sister chromatid of a chromosome has spindle fibers attached to it. These spindle fibers begin to shorten and pull the sister chromatids apart at the centromere. This process of is called disjunction. Now each chromatid is called a daughter chromosome or just a chromosome.

The spindle fibers continue to shorten and move towards opposite ends or poles of the cell. This causes the cell to elongate. The chromosomes during anaphase usually have a distinct V shape. There are also two distinct sets of chromosomes now, and each daughter cell will get one set.

This is a drawing of anaphase and a real photomicrograph of a cell in anaphase. Spindle fibers are green, chromosomes are blue, and kinetochores are pink.
Anaphase Drawing and Photomicrograph

What if Something Goes Wrong?

Sometimes during anaphase, chromosomes will fail to separate properly. This is called nondisjunction. Nondisjunction results in cells with abnormal numbers of chromosomes.

Look at the following image:

During anaphase, these chromosomes should have been split into two equal groups of four. Instead, one pair of sister chromatids failed to split, resulting in one cell with 5 chromosomes and one cell with 3 chromosomes.
Nondisjunction

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
Support