digestive system

• WHAT IS DIGESTION?


  is a process of mechanical and chemical breakdown of food into particles that can be absorbed by cells.
• DIGESTION HAS 2 PHASES?

  1. MECHANICAL PHASE : chewing of food in the mouth and mixed with saliva.
  2. CHEMICAL PHASE : breakdown of food into smaller pieces and mixing with different juices.
• DIGESTIVE TRACT HAVE 2 OPENINGS: mouth, anus,
• digestive system is called as GASTROINTESTINAL SYSTEM
• WHAT ARE THE ORGANS INVOLVED IN DIGESTION?

  ORAL CAVITY

  ESOPHAGUS

  STOMACH

  SMALL INTESTINE

  LARGE INTESTINE

  LIVER

  PANCREAS

  RECTUM

  ANUS
• WHERE DOES DIGESTION START?

  MOUTH

  >is the beginning of digestion.

  >organ of sensation and speech

  >has pairs of salivary glands

  *produce 1 liter per day mostly mealtime

  *produce amylace

  *the ball like mixture of food with saliva is called bolus
• what is the two types of glands?

  parotid glands , sublingual glands
• PAROTID GLANDS

  >largest salivary glands

  >found at sides of face in front of ears

  >if it infect, causes to swell painfully the disease called mumps.
• SUBLINGUAL GLANDS

  >located in the floor of mouth under the tongue
• TONGUE

  >act as an organ of taste

  >used for chewing

  >keeps inner surface of teeth clean

  >used for speech

  >working together to form sounds into words

  *teeth, tongue, hard palate, lips
• TONGUE HAS 4 TYPES PF TASTE WHAT ARE THOSE?

  bitter, sour, salty, sweet
• TEETH

  >is a mechanical break up of food by biting and chewing.
• WHAT ARE THE 4 TYPES OF TEETH?

  *INCISORS - cutting of food ( 8 )

  *CANINE - tearing food ( 4 )

  *PREMOLARS - grinding & crushing ( 8 )

  *MOLARS - pounding ( 12 )
• ESOPHAGUS - help move the food to the stomach

  *30cm long
• PERSISTALSIS ESOPHAGEAL MUSCLES produce an alternating wave like action.

  * after being swallowed, food enters the stomach about 5 second
• STOMACH - storage organ of food.

  * where the food is stored and some digestion occur.

  *food stays in the stomach 3 to 4 hours

  *contain gastric glands
• SMALL INTESTINE - final digestion and absorption of food.

  *3cm in diameter and 7cm long

  *food becomes soupy mixtures.
• LIVER - body's largest gland

  >monitors amount of energy giving glucose in the blood.
• SECRETES BILE - breaks fat into smaller pieces

  *produce 1 liter per day 33ml will be stored in gall bladder
• PANCREAS - lies behind the stomach and upper end of the small intestine

  > secretes insulin

  *hormone that lowers blood sugar lever

  >secretes pancreatic fluid

  *neutralize the acids produce in stomach

  *passes through pancreatic duct

  *leads to the opening with the bile duct

  *this opening is located in the wall of DUODENUM
• LARGE INTESTINE OR COLON - 90% reabsorbed water

  > 7cm in diameter; and 1 1/2 m long

  *after absorption, undigested food will be discharged as waste in the rectum down to anus.
• the 4 stages of digestion

  INDIGESTION - process of taking food into the stomach

  DIGESTION - process of wish food is broken down into smaller simpler substones.

  ABSORPTION - process of taking nutrients from the digestive system into the blood.

  ELIMINATION - process of removing substances that are no further used by the body