digestive system

• Digestive system is mainly responsible for the digestion and absorbtion of the food.
• The mouth is where the process of digestion begins with chewing and mixing of saliva.
• Ingestion is where the food goes into the mouth.
• Mechanical digestion occurs when the teeth break down large pieces of food into smaller ones, which are then mixed with saliva to form a bolus (food ball).
• Chemical digestion starts as soon as the food enters the stomach through gastric juices containing hydrochloric acid that kills bacteria and activates pepsinogen to become pepsin.
• The rounded soft mass of chewed food is bolus.
• Three types of glands parotid, subligual, and submandibular glands.
• Saliva contains an enzyme called ptyalin or amylase.
• Parotid glands are in the inside of the cheeks.
• Subligual glands are below or under the tongue.
• Submandibular glands are glands that are located at the foot of the mouth.
• Soft palate is the tongue and the roof of the mouth. It helps push down the food into esophagus and phayrnx.
• Pharynx connects the mouth to esophagus. It is the passageway for both food and air.
• Epiglottis is the flap which closes the windpipe when swallowing food.
• Esophagus is a muscular tube that connects the stomach.
• Peristalsis is a wavelike muscular contractions. When food has reached the esopagus, it is pushed down further into the stomach.
• Stomach is a muscular expandable organ and receives food from the esophagus.
• Pepsin converts pepsinogen into active form.
• Amino acids and peptides are enzyme pepsin that breaks down.
• Small intestine is where 90% of chemical digestion and absorbtion of food nutrients occur.
• Pancreas is a long narrow gland also the secretion of pancreatic juice. It breaks down into fats, carbohyrdrates, and proteins.
• Gallbladder is a green pear-shaped sac that stores and excess bile.
• Liver is the largest organ of the body in terms of mass. It produces bile (yellowish-brown fluid).
• The large intestine has four parts: cecum, colon, rectum, and anal canal.
• Cecum is the first part of the large intestine. The appendix is attached to it.
• Rectum is the last part of the large intestine. Feces are stored here until they leave the body through the anus.
• Tongue moves food around the mouth by chewing with teeth.
• Salivary glands produce saliva which contains enzyme amylase that breaks down carbohydrates into simple sugars.
• Small Intestine is the longest section of the digestive tract, responsible for absorbing nutrients from food.
• Pancreas is located behind the stomach and pancreatic juice into small intestine to break down carbohydrates, proteins, and fats.
• Stomach secretes hydrochloric acid and pepsinogen which converts to pepsin when mixed with HCl.
• Gallbladder stores bile produced by liver and releases it when needed.
• Large Intestine absorbs water from undigested material and forms feces.
• Appendix is a small thin tube that is not part of the digestive tract.
• Salivary glands is the secrete saliva.
• Rough surfaces in tongue is called papillae.
• Soft palate is the tonge and the roof of the mouth. It helps push the food down to esophagus and pharynx.