The Digestive System
Similarities and Differences in Organ Systems Compared to Humans? Perch Dissection Similarities and Differences in Organ Systems Compared to Humans?
Similarities Differences Gallbladder Liver Pancreas Spleen Pyloric caeca Liver Swim Bladder Pancreas Spleen
Pyloric Caeca
Digestive System Animation http://www.medtropolis.com/VBody.asp
Digestive System Parts Mouth Esophagus Stomach Liver Gallbladder Pancreas Small Intestine Large Intestine Rectum and Anus
Mouth Physical Digestion – chewing 32 teeth Tongue 12 molars, 8 premolars, 4 canines, 8 incisors Tongue Taste buds distinguish between type of food Moves food around forming bolus Chemical Digestion – salivary amylase
Teeth and Taste Buds
Esophagus
Esophagus Receives bolus from the pharynx Moves bolus to stomach by peristalsis http://www.scoe.com/images/Esophagus1.jpg
Stomach
Stomach Receives bolus from the esophagus through the lower esophageal sphincter Mixes the food with gastric juices containing HCl Mucus helps protect the stomach lining Pepsin - a digestive enzyme, helps break down large protein molecules Creates a mixture called Chyme which is moved through the pyloric sphincter to the small intestines
Liver
Liver Releases bile which emulsifies fats and help absorb fatty acids, cholesterol and some vitamins Stores carbohydrates and vitamins and detoxifies many harmful substances http://www.healingdaily.com/conditions/cirrhosis-liver.jpg
GallBladder
Gallbladder Stores bile that is produced by the liver Gallstones – crystallized substances from bile in the gallbladder Can result in surgery to remove gallbladder
Pancreas
Pancreas Secretes digestive enzymes Neutralizes chyme Secrete Hormones: Insulin – lowers blood sugar levels Glucagon – raises blood sugar levels
Small Intestine
Small Intestine 9 to 10 feet long Composed of 3 parts : duodenum, jejunum and the illeum Most important absorbing organ Digestion is completed in the small intestine http://www.scoe.com/images/Stomach1.jpg
Large Intestine
Large Intestine Also called the colon Comprised of 4 sections Ascending, Transverse, Descending and Sigmoid Little or no digestive function Chyme becomes feces which is stored until elimination
Rectum and Anus
Rectum and Anus Rectum – temporary storage facility for feces Internal and External sphincters allow feces to be passed by muscles pulling the anus over the feces