Digestive System

• Digestion - the process by which food is broken down into smaller components
• Absorption - the body can absorb to nourish its cells
• The digestive system consists of organs that work together to break down food, extract nutrients, and eliminate wastes.
• Elimination - waste products are eliminated from the body
• Accessory Organ - assist in food digestion contains: salivary glands, liver, gallbladder, pancreas.
• Alimentary Canal - contains organs where food passes through contains: mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus
• Accessory Organs

  • Salivary Glands

  • Liver

  • Gallbladder

  • Pancreas
• Alimentary canal

  • Mouth

  • Pharynx

  • Esophagus

  • Stomach

  • Small Intestines

  • Large Intestines

  • Rectum

  • Anus
• Saliva is produced by three pairs of major salivary glands (parotid, submandibular, and sublingual) and many minor salivary glands throughout the oral cavity.
• Liver produces bile which helps emulsify fats into smaller droplets for easier digestion by lipases.
• Mechanical Digestion - happens in the mouth, changing the size of food by tearing, grinding, and cutting it
• Chemical Digestion - happens in the mouth, stomach and small intestine, changing the chemical composition of the food with the help of enzymes
• Peristalsis - a wavelike contraction of esophagus
• Ingestion - the process which the body take in food through the mouth for digestion, absorption, and elimination
• Bolus - combination of food and saliva
• Parts of Digestive System

  A) mouth

  B) pharynx

  C) esophagus

  D) liver

  E) gallbladder

  F) stomach

  G) pancreas

  H) small intestines

  I) anus

  J) rectum

  K) large intestine

  
• Esophagus - muscular tube that carries swallowed food from the pharynx to the stomach
• Mouth - where ingested food is mechanically broken down into smaller pieces.
• pharynx - also known as throat; passage between mouth, nose and esophagus and is used in digestive and respiratory system
• small intestine - absorbs nutrients from food where final digestion occur; known as the longest part of digestive system
• anus - opening at end of digestive tract through which feces are eliminated
• Rectum - storage area for waste material
• Liver - largest gland in body that produces bile to aid in fat digestion
• PARTS OF SMALL INTESTINE

  A) Duodenum

  B) jejunum

  C) ileum

  
• PARTS OF LARGE INTESTINE

  A) ascending colon

  B) transverse colon

  C) descending colon

  
• large intestine - reabsorbs water from undigested food; last section of digestive tract; also known as colon
• CARBOHYDRATES - starts being digested in the mouth and ends in the small intestine
• PROTEIN - starts being digested in the stomach
• FAT - starts being digested in the small intestine
• carbohydrase is an enzyme that breaks down carbohydrates into simple sugar
• proteinase breaks down protein into amino acids
• lipase breaks down fats into fatty acids and glycerol
• pepsin is produced by chief cells in gastric glands, it converts proteins to peptides
• Fiber is a type of carbohydrates found in plants that we do not digest
• villus - move nutrients from lumen (opening) of the intestine into the circulatory system