The heart pumps blood, the liver is the "filter" it filters out alcohol, drugs, salt, etc. Brain has many different parts including memory, CNS (central nervous system - automatic system, you do not have to think about things controlled by CNS such as digestion, coughing, breathing, blinking, reflexes and many others, nervous system - we can control our arms and legs, the nerves send messages to the brain then brain interprets). Pancreas produces bile which aids in digestion. Saliva (in your mouth) also helps carbohydrate digestion by producing enzyme, as you chew bread it gets sweeter because the amylase breaks down carbs into simple sugars. Let me know what else you need to know.