Lesson 19 What is meiosis?

As you know, in asexual reproduction, there is only one parent. The chromosomes duplicate themselves, and the offspring are exactly like the parent.

Sexual reproduction is different. There are two parents. That means two sets of chromosomes. One from Mom, and one from Dad.

There are ways I am like my Dad And some ways like Mom

The chromosomes in body cells are paired. One from Mom and one from Dad. The chromosomes in sex cells are NOT paired. Therefore, sperms and eggs have half the chromosomes as body cells.

The color of these chromosomes was added to show the pairings.

This purple one is from Dad This one from Mom

When fertilization takes place, the sperm chromosomes join the egg chromosomes. Together, they add up to the full number of chromosomes in the body cells.

Since chromosomes carry traits, the zygote has traits from both Mom and Dad.

Reproductive cells, or gametes, develop in special organs of your body. The process by which gametes form is called meiosis.