How does crossing-over increase variation in genes?

Question

abb0t · Answer

Imagine that you have a read sweater and a blue sweater. If you took the sleeve OFF the red sweater and sewed it onto the blue sweater. And then you took ONE of the sleeves of the blue sweater and sewed it onto the red. You have two different sweaters. 

Now, imagine that you did that with a sweater that had a rainbow sleeves and you mixed them together. You get different sweaters that you can sell.

anonymous · Answer

Umm that kinda makes sense

abb0t · Answer

Ok, picture this hypothetical situation. Say we get surgery and decide to surgically remove our arms and switch them. That means you will have my left arm and I will have yours. 

Now, if we switch arms, we are not DIFFERENT. I am carrying your arm, which may have no hair, painted nails, and smaller fingers. While you have my arm, that has tattoo's and hair, and ogre nails, etc., 
Now, we are genetically different. Does that help? We are the same persons, but we just carry different information on our bodies.

abb0t · Answer

if you decide that you didn't like my ogre fingers, and you switched them with someone else who had better fingers, then now you have my arms, but different fingers. 
Crossing over is similar to that. Over time, as you change genetic information with different people, you get more variation, because you are only crossing over portions of your arm!

Same with genes. As we continue to cross-over, you will eventually get an arm with different elbows, fingers, nails, tattoo's, etc.,

anonymous · Answer

ohhh i see okay thank you so much genius xD

anonymous · Answer

Could you sum it down to a could sentences for me?

anonymous · Answer

couple*