The Digestion System

SBI3U NAME:______The Digestion System

General Characteristics Two types: Physical: Chemical:

• Role of organ systems such as the digestive system is to maintain ______: a

• Remember, systems ______à as we learn, make a mental note of the ______of the digestive and circulatory systems

• The digestive tract is also called the ______or the ______à a ______open at ______(______and ______)

• Role is to:

Structures and Functions

• Consider that the inside (or ______) of the alimentary canal is actually ______.

• It is highly specialized to ______and ______it into the ______system

Structure of the Wall of the Digestive System

• The inside space of the tube is the ______

• The entire canal has the same ______.

• The layers are ______depending on the importance for digestion at that point

• See handout diagram

Function of the Layers

• Mucosa

• ______lining (direct contact with ______)

• starts with layer of ______mixed with ______and ______secreting cells

• forms ______– most pronounced in the ______(includes ______) SBI3U NAME:______• houses special ______that help fight ______(especially in the ______)

• has a base of ______

• Submucosa

• ______tissue to connect mucosa to ______

• contains ______(ie mucus), ______vessels and ______vessels for ______transport

• Muscularis

• ______layer

• ______layers in opposite directions, ______

• inner layer ______the GI tract and ______

• outer layer ______with GI tract and ______

• only 1 layer in the Peritoneum ______

• ______muscle for control

• houses main GI tract nerves

• Peritoneum/Serosa

• Serosa is strong ______tissue that surrounds the GI tract. Connected to the serosa is a thin outer layer of cells called ______that support the abdominal organs. SBI3U NAME:______Steps in Digestion

• 1) ______– acquire food from the environment

• At this point food is ______to be used by the body

• Food must be converted to ______that can pass through the walls of the ______

• 2) ______– preparation of food for absorption

• i.e. must turn carbohydrates into ______like glucose or fructose (called monosaccharide)

• Starch (______) à many subunits

• Not ______

• To Maltose (______) à two subunits

• Absorbable

• To Glucose (______) à one subunit

• ______

• Solid food is ground up, ______

• Mostly in ______

• This helps increase the surface area for ______digestion

• Teeth

• Incisors – ______

• To ______

• ______included here(largest in ______)

• Molars – ______SBI3U NAME:______• ______

• Works on ______components of food

• Food is mixed with various ______from digestive ______and then ______act upon the broken-down food

• Creates a ______

• 3) ______

• Mostly in ______

• In ______intestine only ______and ______absorbed

• 4) Elimination

• Through ______and ______

• Part of food not used SPECIALIZED DIGESTIVE SYSTEMS