Pancreas
It is a large gland behind in the stomach that secretes digestive enzymes in the duodenum. Inside the pancreas are Islet of Langerhans. It is considered as an endocrine gland producing various hormones. Pancreas also produce pancreatic enzymes that act as digestive enzyme that assist in digestion and absorption of nutrients in the small intestine. These helps to break macromolecules such as carbohydrates, proteins and fats.
Answer:
A dam that could allow fish to still pass through is a fishway/fish pass its a "fish ladder" that is structured on or around artificial or natural barriers to allow for fishes natural migration and the movement for potamodromous species.
The major differences are that fats are solid at room temperature while oils are liquid, and that oils are usually of plant origin while fats are of animal origin.