Final answer:
Unsaturated fats have double bonds between carbons in the chain, resulting in fewer hydrogen atoms attached to the carbon chain compared to saturated fats.
Step-by-step explanation:
Unsaturated fats have double bonds between carbons in the chain. These double bonds result in fewer hydrogen atoms attached to the carbon chain compared to saturated fats. Monounsaturated fats have one double bond, while polyunsaturated fats have more than one double bond.