Gametes: Definition, Formation & Fusion

Lesson Transcript
Instructor: Kelly Robson

Kelly has taught High School Science and Applied Communications. She holds an Education Specialist Degree in Ed. Leadership.

Gametes are the cells that fuse together during sexual reproduction to form a new organism. This lesson covers what these cells are, what they do, and the end result of when they meet.

Definition of Gametes

Gametes are the reproductive cells used during sexual reproduction to produce a new organism called a zygote. The gametes in males and females are different. The male gamete is called sperm. It is much smaller than the female gamete and very mobile. It has a long tail, flagellum, that allows it to move towards the female gamete. The female gamete is called an egg or ova. It is much larger than the sperm and is not made to move.

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Genetic Drift: Definition, Examples & Types

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

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:01 Definition of Gametes
  • 0:30 Formation of Gametes
  • 1:32 Fusion
  • 2:39 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

Formation of Gametes

Both the male and female gametes are formed during a process of cellular reproduction called meiosis. During meiosis, the DNA is only replicated or copied one time. However, the cells are divided into four separate cells. This means that the new gamete cells have only half of the number of chromosomes as the other cells. So, during meiosis, DNA or chromosomes are copied, then split into two cells (with one full set of chromosomes each), then again split into two more cells, leaving only half of the pairs of chromosomes in each new cell.

These new cells with only half of the chromosomes will mature into the gametes. The gametes are haploid cells because they have only one set of chromosomes. When they unite they will join their single sets of chromosomes to make a complete set, and then they will be considered diploid cells. In the female, the eggs or ova mature in the female's ovaries. The sperm will mature in the male's testes.


During sexual reproduction, a male and female gamete will merge together to form a new organism. The two haploid cells will fuse together to form a diploid cell called a zygote. The zygote will undergo massive cellular reproduction and develop into a new individual organism with half of the chromosomes from the mother and half from the father.

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