Name: Apoptosis | Cell division | Biology | Khan Academy
Uploaded: 2016-10-06T14:17:37.000Z
Duration: 10 min 48 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

- [Voiceover] So we're here today to talk about apoptosis.

I was gonna ask you some questions about it,

you were going to explain what it even is to me.

- [Voiceover] Absolutely. - [Voiceover] Okay.

I did a little bit of etymology research.

'cause it comes from Greek particles that I identified.

So we have, here's the limit of what I know right now.

and "ptosis," which means, like, a falling.

And my understanding is that this programmed cell death,

is kind of analogous to leaves falling away from a tree,

that it's something that's supposed to happen,

and the cells just die in this prescribed way

This is something that the cell embarks on

- [Voiceover] Yeah, I think that's a really,

and I think that is why it was named apoptosis

by some of the first folks who studied it,

So it's very much a normal and healthy thing

that your body is actually doing right now.

- [Voiceover] Right now. - [Voiceover] Oh man.

So, okay, so what are the ways in which a cell can die?

What are, I mean, 'cause we have this diagram here.

what looks like the aftermath of some kind of explosion.

two very broad categories of ways that a cell can die,

- [Voiceover] Okay. - [Voiceover] But more,

where the cell basically swells up and explodes,

because those can damage other cells in the area,

they can attract cells of the immune system

and here you actually see the cell shrinking down

- [Voiceover] And that's these little orange things in here

into little fragments encircling different cell components.

So you can sort of see those starting to bud off.

whose job is basically to gobble up debris,

they're gonna come and eat those little fragments,

and it's gonna be like nothing ever happened.

- [Voiceover] So this is kind of the difference

between disposing of your garbage in trash bags

by just dumping it out the window of your apartment.

If you dispose of your garbage in trash bags,

- [Voiceover] So other cells can use those components

from having nasty stuff floating around outside.

- [Voiceover] So what are the circumstances