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.
4 because if you have a infection it causes you not to breath properly
Similar to those performed by the cell organelles in group b
Commensalism is when one organism benefits off the other one without harming it. Examples are tree frogs that use plants for protection or jackals that have been expelled from packs trailing tigers and feeding on the remains of its kill. Barnacles on whales get shelter by attaching to a whales body