Saturated lipids are those lipids in which only single bonds are found between the carbon-carbon atoms of hydrocarbon chains.
Triglyceride is a type of lipid, which is a main constituents of the body fat in human beings and other animals. This molecule is composed of a glycerol backbone by which three fatty acid molecules are attached,
The given structure represent a saturated triglyceride as it has only single bonds between carbon-carbon atoms.
My guess would be H₂O/ water, since osmosis is a form of passive transport and I can't see the model the question references. Gases like O₂/ oxygen, CO₂/ carbon dioxide, and simple sugars like glucose can also pass through a cell membrane with passive transport though.
