Day 1 Digestion
"No legacy is so rich as honesty."
William Shakespeare

Obj. 1
Functions of the Digestive
System
• Break down macromolecules found in food into smaller parts
• Absorb nutrients into circulatory
& lymphatic systems

Obj. 1: Alimentary Canal
• The continuous hollow tube that extends from the mouth to the anus

• Mouth (Oral Cavity)
• Esophagus
• Stomach
• Small Intestine
• Large Intestine

• Organs and glands which lie outside of the alimentary canal, but assist the process of digestive breakdown

Accessory Organs:
Examples
• Liver
• Pancreas
• Gall Bladder
• Teeth/Tongue

What is the difference between the alimentary canal and the accessory organs?

Are these organs in the A.C. or are they accessory organs?
• Stomach
• Liver
• Esophagus
• Large Intestine
• Gall Bladder
• Mouth
• Pancreas

Are these organs in the A.C. or are they accessory organs?
• Stomach – A. C.
• Liver – Accessory
• Esophagus – A. C.
• Large Intestine – A. C.
• Gall Bladder – Accessory
• Mouth – A. C.
• Pancreas – Accessory

Today’s Agenda
1. Objective 2
2. Teeth: Obj. 5
3. Saliva, Chewing &
Swallowing: Obj. 7-8
4. Intro to the Stomach

Obj. 2: Major Digestive
Processes
• Ingestion
• Propulsion
• Mechanical Digestion
• Chemical Digestion
• Absorption
• Egestion

• Peritoneum is the serous membrane lining the interior of the abdominal cavity & covering the surfaces of abdominal organs

• Includes the omenta and the mesentary

• Mechanical Breakdown
–Mastication
• Chemical Breakdown
–Salivary Amylase:
Carbohydrates

Obj. 5
Tooth Structure

Obj. 5 cont
Tooth Structure
• Enamel: acellular, brittle, mineralized
• Dentin: bonelike material, forms bulk of tooth
• Pulp: supplies nutrients & provides tooth sensations
• Cementum: calcified connective tissue

Obj. 5 cont
In each of the next frames, what part of the tooth is being effected?

Obj. 5 cont
Deciduous & Permanent Teeth
•

Obj. 5
• Also called baby or milk teeth
• 20 teeth by 2 years old

Permanent Teeth
• 32 teeth, start erupting by 6-7 yrs old
• Dental Formula: Right
Left
• 2I, 1C, 2PM, 3M X 2 = 32 teeth
2I, 1C, 2PM, 3M
• Incisors, Cuspids, Bicuspids, Molars

Teeth
• How many permanent teeth do you have if you had your wisdom teeth taken out?
• What is the hardest part of the tooth?
• Name the 4 categories of teeth.
• Where is the root canal of the tooth located?
Go to 7 show

Today’s Agenda
• Review
• Quiz
• Cat Dissection Lab
• Stomach:
–Notes on Obj. 6, 9 & 10

Review
• Name the organs of the alimentary canal and the accessory organs.
• What are the differences between deciduous and permanent teeth?
• How does saliva help you to digest your food?

Review
**Take a look at your digestive diagram**

QUIZ

Cat Dissection Lab

Today’s Agenda 2/28
• Stomach: Obj. 6, 9 & 10
• Small Intestine: Obj. 6,
11, & 12

Functions of the Stomach
• Mechanical Breakdown
– Food is liquefied
– Mixing
• Chemical Breakdown
– Protein digestion (Pepsin)
 Final Result: Chyme
Gastric juice?

Obj. 9: Gastric
Juices
• 3-4 L/day
• HCl produceds by parietal cells
• Zymogenic cells secrete pepsin.

Obj. 10 Regulation
• Cephalic phase- sight, smell
• Gastric phase-stomach distension and pH
• Intestinal phase-food reaches small intestine, stimulates

The Stomach
• How is the stomach designed to do its job?
• Name the 3 different phases of stomach regulation and how each effects hunger.
• What is in gastric juice?

• Duodenum
• Jejunum
• Ileum

Functions of the Small
Intestine
• Mixes chyme with bile, pancreatic juice, and intestinal juice
• Propels food to the large intestine

Functions of the Small
Intestine
• Digestion and Absorption of:
–Carbohydrates
–Proteins
–Lipids
–Nucleic Acids

Nutrients are actively transported from microvilli to the bloodstream:

Objective 11: Absorption in the small intestine
• Complete the handout entitled
– “Digestion in the the small intestine” to cover the information as to how nutrients are absorbed in the small intestine.

Today’s Agenda
• Obj. 12 Notes
• Stomach Acid Review
• Antacid Lab

Obj. 12: Role of bile, bicarbonate ions in pancreatic juice
• Bile:
•Made continuously in liver and stored in gallbladder
•Contains electrolytes, bile salts, bile pigments
•Enters at duodenum
•Fuction: Emulsifies lipids

Obj. 12: Role of bile, bicarbonate ions in pancreatic juice
• Bile:
•Fuction: Emulsifies lipids

Obj. 12: Role of bile, bicarbonate ions in pancreatic juice
• Bicarbonate Ions:
– Fuction: neutralizes the acidic chyme
– Act as buffers to prevent large pH changes
• The release of bile and bicarbonate ions are controlled by hormones

• What’s in your gastric juice?
• What’s heartburn?

• Finish Small Intestine WS and
Lab
• Obj. 14: Large Intestine
• Large Intestine Disorders

Obj. 14: Structure & Function of
Large Intestine
• Functions include: a. Absorption of water b. Absorption of electrolytes c. Absorption of vitamins (B&K) made by bacteria d. Defecation

Obj. 14 (cont.)
•
Defecation is triggered by feces entering the rectum .
• The walls of the rectum contract to move stool.
• Movement is aided by the
Valsava maneuver . In this maneuver we close the glottis, contract the diaphragm and abdominal walls to create pressure distally.

Functions of the Liver
• Produces bile and other digestive enzymes

Function of Gall Bladder
• Stores and releases bile

Function of the Pancreas
• A gland that produces many digestive enzymes and bicarbonate