How does a membrane bound organelle differ from a non membrane bound organelle

Membrane bound organelles have bilipid membranes surrounding them just like the cell does. These would include the nucleus, mitochondria, etc. Non-membrane bound organelles do not. Off the top of my head, I am not thinking of what actually could be considered in this category except maybe ribosomes.

I like this question better than the bacteria question. An organelle is a cellular structure that has a unique function. It should be something more than a macromolecular complex, like a ribosome.

Ribosomes and centrioles are sometimes called non membrane bound organelles. They are large, protein-rich structures within a cell that have a unique function. They are not surrounded by phospholipid bilayers either.

Membrane-bound organelles have a phospholipid bilayer surrounding an internal environment. Lysosomes, peroxisomes, and the Golgi are examples of these.