April 2, 2014 1. DO NOT TOUCH Bob the skeleton OR Junior the Organ model. 2. What is the function of...
-
Upload
julianna-benson -
Category
Documents
-
view
214 -
download
1
Transcript of April 2, 2014 1. DO NOT TOUCH Bob the skeleton OR Junior the Organ model. 2. What is the function of...
April 2, 2014
• 1. DO NOT TOUCH Bob the skeleton OR Junior the Organ model.
• 2. What is the function of the Digestive System?
• 3. Can you name all the organs in the digestive system?
The Digestive System
Hey- chew on this! We’ve made it to the..
Functions
• Ingest food
• Break down food
• Move through digestive tract
• Absorb digested food and water
• Eliminates waste materials
There are 3 Macronutrients
• Carbohydrates (Carbs)
• Proteins (ex: meat)
• Lipids (fats)
Carbohydrate
Protein
Fat (aka: Lipids)
• Gastrointestinal System• Function-physical and
chemical breakdown of food
• Accessory organs: Salivary glands, tongue, teeth, liver, gallbladder, and pancreas
Mouth
• Mouth- physical and chemical breakdown.
• Physical Digestion: chewing
• Chemcial Digestion: Saliva contains enzyme amylase to break down carbohydrates
Mouth
• Breaks down food into small pieces
• Begins starch digestion (amylase)
• Saliva produces amylase and lubricates food
• Moves food into esophagus
• Epiglottis covers trachea
• Peristalsis moves food to stomach
• Pharynx- contains opening to trachea as well.
• Epiglottis covers opening of trachea.
• Esophagus- the tube you swallow food with.
• Uses peristalsis – wave-like motion to push food down.
Peristalsis
The wave-like squeezing action of muscles that is used to move food along
http://www.lionden.com/peristalsis.htm
Esophagus- transverse view
• Sphincter-a circular muscle sqeezes shut
• Food sits in stomach for 1-4 hours. Gastric (stomach) juices contain hydrochloric acid- activates pepsin, kills bacteria.
• Small intestine: not so small! 20ft x 1’’
• Small intestine has lots of enzymes called peptidases
• Digested food is absorbed into the bloodstream.
• Large intestine- 5 ft x 2’’.
• Final absorption of water, storage of indigestible material, absorption of vitamins B and K by bacteria.
• Colon connects to rectum- anal canal opens to the anus (final opening). This is where your poop sits before… you “sit” ;) .
But Wait! What about the accessory organs: Liver, gall bladder and pancreas • Liver- largest gland in
your body• Secretes bile- digests
fat.• Detoxifies blood
• Gall bladder- stores and concentrates bile (which digests fats)
• Pancreas- produces insulin. – Insulin regulates the
uptake of glucose by the cells