Question

Our cells all have pretty much the same organelles.

They all have a nucleus, golgi complexes, some ribosomes, some mitochondria, etc.

You get it?

But they don't all have the same NUMBER of organelles.

Some of our cells are very busy, and they have to do a lot of work.
Our liver cells and our kidney cells, for example, are "busy cells." They have to work pretty hard.
So, because of that, they have a greater number of mitochondria. HUNDREDS of mitochondria.

You remember that mitochondria are sometimes call the cells' "powerhouses"?