Chapter #10

Digestion

Chapter 10.1 Notes

• The digestive system is a group of organs that take in food and change it into a form the body can use.

• Digestion is the changing of food into a usable form.

• Physical change occurs when large food is broken down into little pieces. Chewing, grinding.

• Chemical change turns food into a form that cells can use called molecules.

• Enzymes are chemicals that speed up the rate of chemical changes.

• Starch changes to glucose by a chemical change.

Chapter 10.2 Notes• Water, vitamins, and mineral can move

directly from your digestive system into your body cells without being changed.

• Fats, proteins, and carbohydrates must be acted upon by enzymes to be digested.

• Saliva is a liquid that is formed in the mouth and that contain enzymes that breakdown carbohydrate.

• Salivary Glands are 3 pairs of small glands located under the tongue and behind the jaw.

• Mouth 1 minute physical change to food and enzyme that breaks down carbohydrates.

• Esophagus 1 minute• Stomach 4 hours makes enzymes and HCl

Hydrochloric acid break down protein.• Small intestine 12 hours where most of digestion

takes place. • Villi fingerlike parts on the lining of the sm.

Intestine.

• Pancreas makes 3 different enzymes to breakdown fat, protein, and carbohydrates.

• Liver the largest organ in the body makes bile. Bile is a green liquid that breaks down fat (Physical Change).

• Gallbladder is a small baglike organ that stores bile located under the liver.

Food does NOT pass

through these

organs

• Large Intestine 5 hours main job is to remove water from digested food.

• Anus where solid waste leaves the body.

• Appendix is a small fingerlike part found where the small and large intestine meet. Does not effect digestion.

• Digestive system is about 5 times as long as your body (900 cm)

• Diffusion is how food gets into the blood.

• Animals that eat plants have longer digestive systems than meat eaters.

• Simple animals only have 1 opening in the digestive system (hydra, jellyfish, planarian)

• Tapeworms have no digestive system.

• Ulcer stomach lining being digested

• Mucus is a thick, sticky material that protects the stomach and intestinal lining from enzymes and HCl.

• Heartburn caused by stomach acids moving into the esophagus.

• “The stomach”. January 26, 2007. http://wappingersschools.org/RCK/staff/teacherhp/johnson/visualvocab/stomach%5B1%5D.jpg

• “The Digestive System”. January 26, 2007. http://www.teachnet.ie/farmnet/images/Digest3.gif

• “Heartburn”. January 29, 2007. http://www.webmd.com/NR/rdonlyres/16E42462-463A-44A2-B2D1-7D5AC35CF6E0.jpg