Name: ______Pd: ______Date: ______

Unit 6: The Digestive System

The Digestive System

  1. Digestion
  2. Breakdown of ______food
  3. Absorption of nutrients into the blood
  4. Metabolism
  5. Production of ______energy (ATP)
  6. Constructive and ______cellular activities

Organs of the Digestive System

A. Two Main Groups

  1. ______Canal or Gastrointestinal Tract (GI Tract)
  2. Continuous ______hollow tube
  3. Accessory digestive organs
  1. Mouth
  2. Anatomy
  1. ____ (Labia) – protect the anterior opening
  2. Cheeks – form the ______walls
  3. Hard ______ – forms the anterior roof
  4. Soft Palate – forms the posterior ______
  5. Uvula – Fleshy projection of the soft palate
  6. Frenulum – a fold of mucous that secures the ______to the floor and limits its posterior ______
  7. ______ – space between lips externally and teeth and gums internally
  8. Oral Cavity – area contained by the teeth
  9. Tongue – attached at ______and styloid ______of the skull, and by the lingual frenulum
  10. Tonsils – part of the body’s defense system
  11. When the tonsils are ______and enlarged, they block the entrance to the ______, making swallowing difficult
  12. Found in the posterior end of the oral cavity
  13. Palatine Tonsils and Lingual Tonsils
  14. Processes of the Mouth
  15. ______(chewing)
  16. Mixing masticated food with saliva
  17. Initiation of swallowing by the tongue
  18. Allowing for the ______of taste

C. Digestive Activities of the Mouth

  • Mechanical ______
  • Food is physically broken down by chewing
  • Chemical ______
  • Food is ______with saliva
  • Breaking of ______into ______by salivary amylase
  1. Pharynx (______)
  2. Anatomy
  3. Nasopharynx – ______of the digestive system
  4. Oropharynx – posterior to the oral cavity
  5. Laryngopharynx – below the oropharynx and connected to the ______
  6. Functions
  7. Serves as the passageway for ______
  8. Food is ______to the esophagus by two muscle layers
  9. Longitudinal inner layer
  10. Circular outer layer
  11. Food ______happens by alternating contractions of the muscle layers (peristalsis)
  1. Esophagus
  2. Anatomy
  3. Also called the ______
  4. Runs from ______through the diaphragm
  5. Conducts food by ______(slow rhythmic squeezing)
  6. Passageway for _____only (Respiratory system branches off after the pharynx)

Digestive Activities of the PharynxEsophagus

  • These organs have ______
  • Serve as ______to the stomach
  • ______: swallowing & peristalsis
  1. Stomach
  2. Anatomy
  3. C-Shaped, Located on the ______side of the ______cavity
  4. Nearly hidden by the ______and diaphragm
  5. Cardioesophageal Sphincter
  6. Where food ______
  7. Pyloric sphincter controls food movement from the stomach into the small intestine
  8. Regions
  9. ______region – near the heart
  10. Fundus and Body
  11. Pylorus – funnel-shaped terminal ____
  12. Food ______into the SI at the ______sphincter
  13. ______– internal folds of the mucosa
  14. External Regions: Lesser curvature, Greater curvature
  1. Stomach Functions
  2. Because of ______, the food can move, & also churn, ______, & pummel food, breaking it into smaller particles
  3. Act as a ______for food
  4. ______food breakdown
  5. *Chemical breakdown of ______ begins here
  6. Stomach Facts
  7. Full – it can hold ______of food
  8. Empty – it ______on itself, mucosa forms folds called ______

E. Digestion and Absorption in the Stomach

  • Protein digestion ______
  • Pepsin – an active protein digesting enzyme
  • Rennin – works on digesting milk protein
  • The only ______that occurs in the stomach is of ______&aspirin

F. Propulsion in the stomach:

  • Food must first be ______
  • Rippling ______occurs in the lower stomach
  • The stomach empties in ______hours

G. Food Breakdown in the Stomach

  • ______juice is regulated by ______and hormonal ______
  • Presence of food or falling pH causes the ______of gastrin
  • Gastrin causes ______to produce protein-digesting enzymes
  • Hydrocholoric acid makes the stomach contents ______
  1. Small Intestine (SI)
  2. Anatomy
  3. The body’s major ______organ
  4. Site of nutrient ______ into the blood
  5. ______tube extending from the pyloric sphincter to the ileocecal ______
  6. ______from the posterior abdominal wall by the mesentery
  7. Longest section of the alimentary ______& average length is 7-18 ______!
  8. Subdivisions
  9. ______ – attaches to the stomach & curves around the head of the pancreas
  10. ______ – attaches anteriorly to the duodenum
  11. ______ – extends from jejunum to large intestine
  1. Chemical Digestion in the Small Intestine
  2. Sources of enzymes that are mixed with ______
  3. Intestinal ______and ______
  4. Bile enters from the ______
  5. Villi – fingerlike structures formed by the mucosa that gives the SI more surface area
  6. ______ – small projections of the plasma membrane; found on absorptive cells
  7. Absorption in the Small Intestine
  8. Structures involved: ______, blood capillaries, ______

D. Digestion in the Small Intestine

  • ______from the brush border
  • Break ______sugars into simple sugars
  • Complete some ______digestion
  • ______enzymes play the major digestive function
  • *Help ______digestion of ______
  • Carry out ______of all protein digestion
  • Responsible for ______digestion
  • Digest ______acids

E. Absorption in the Small Intestine

  • Water is absorbed along the length of the SI
  • End ______of digestion
  • Most substances are absorbed by ______through cell membranes
  • Lipids are absorbed by ______
  • Substances are transported to the ______by the hepatic portal vein or lymph

F. Propulsion in the Small Intestine

  • Peristalsis is the major means of moving food
  • Segmental movements
  • Mix ______with digestive ______
  • Aid in ______
  1. Large Intestine (LI)
  2. Anatomy
  3. Larger in diameter, but shorter than the SI
  4. Frames the ______abdomen
  5. Average length is 1.5m or ______long
  6. It extends from the ileocecal valve to the anus
  7. Cecum – sac-like ______part of the LI
  8. Appendix
  9. ______from the ______
  10. Bacteria can accumulate & multiply causing appendicitis, inflammation of the appendix
  11. Accumulation of lymphatic tissue that sometimes becomes inflamed (appendicitis)
  12. Colon
  13. Ascending - travels up the ______side of the abdominal cavity and turns
  14. Transverse - continues ______the turn
  15. Descending - continues down the ______side
  16. S-shaped sigmoidal - enters the ______and is s-shaped
  17. Rectum
  1. Anus
  2. External body ______
  3. The anal canal has an external ______sphincter composed of skeletal muscle
  4. It also has an ______involuntary sphincter formed by smooth muscle
  5. These sphincters act to ______& close
  6. Closed most of the time, it is only open during defecation, when feces are ______from the body
  7. LI contains ______cells that produce mucus to act as a lubricant to ease the passage of feces
  8. Sigmoid colon, rectum, and anus lie in the pelvic region
  9. Functions of LI
  10. ______of water
  11. Eliminates ______food from the body as feces
  12. Does not participate in digestion of food
  13. Goblet cells produce ______to act as a lubricant

C. Food Breakdown & Absorption in the LI

  • No digestive ______are produced
  • Resident bacteria ______remaining nutrients
  • Produce some vitamin K and B
  • Release ______
  • Water and vitamins K and B are ______
  • Remaining ______are eliminated via feces

D. Propulsion in the Large Intestine

  • ______peristalsis
  • Mass movements of food
  • Slow, ______movements
  • Occur _____ to _____ times per day
  • Presence of feces in the rectum causes a defecation reflex
  • Internal anal sphincter is relaxed
  • Defecation occurs with relaxation of the voluntary (external) anal sphincter
  1. Accessory Digestive Organs
  2. Salivary glands
  3. Saliva-producing glands
  4. Parotid glands – located anterior to ears, becomes inflamed with the ______
  5. Submandibular glands
  6. Sublingual glands
  7. ______- Mixture of mucus and serous fluids to help to form a food bolus
  8. Contains salivary amylase to begin ______digestion
  9. Dissolves ______so they can be ______
  10. Teeth
  11. The role is to masticate (chew) food
  12. Humans have _____ sets of teeth
  13. ______(baby or milk) teeth
  14. 20 teeth are fully formed by age _____
  15. ______teeth
  16. Replace deciduous teeth beginning between the ages of 6 to 12
  17. A full set is ______teeth, but some people don’t have ______teeth
  18. Classification of teeth
  19. Incisor, Canine, Premolar, Molar
  20. Pancreas
  21. Produces a wide spectrum of digestive enzymes that break down ______of food
  22. Enzymes are secreted into the ______
  23. Alkaline fluid introduced with enzymes neutralizes ______chyme
  24. Endocrine products of pancreas
  25. Insulin and Glucagons
  26. Liver
  27. ______in the body
  28. Located on the ______side of the body ______the diaphragm
  29. Has many functions; its digestive function is to ______
  30. Connected to the gall bladder via the common hepatic duct
  31. Bile
  32. Produced by ______in the liver
  33. Bile salts and pigments, cholesterol, Phospholipids, and Electrolytes
  34. Conditions of the Liver
  35. Hepatitis – inflammation of the liver – caused by ______infection
  36. ______ – inflammatory condition in which liver is severely damaged & becomes hard & fibrous
  37. Likely when someone drinks alcohol excessively for many years
  38. Gall bladder
  39. Small, thin-walled green sac that fits in a shallow fossa in the inferior surface of the liver
  40. It stores ______& removes ______
  41. When fatty foods enter the duodenum, a hormone ______the gallbladder to ______& spurt out stored bile
  42. If bile is stored for too long or too much water is removed, the cholesterol it contains may ______and form gallstones
  43. ______are sharp, and when the gallbladder contracts, it causes extreme ______or a gallbladder attack

Processes of the Digestive System

1. Ingestion – getting food into the ______

2. Propulsion – moving foods from ______of the digestive system to another

3. Peristalsis – alternating ______of contraction

4. Segmentation – moving materials ______& ______to aid in mixing

5. Mechanical digestion (examples)

  • ______of food in the mouth by the tongue
  • ______of food in the stomach
  • Segmentation in the small intestine

6. Chemical Digestion (examples)

  • Enzymes ______food molecules into their building blocks
  • Each major food group uses different enzymes
  • Carbohydrates are broken to simple sugars
  • ______are broken to amino acids
  • Fats are broken to fatty acids and alcohols

7. Absorption

  • End ______are absorbed in the ______or lymph
  • Food must enter mucosal cells and then into ______or ______capillaries

8. Defecation

  • Elimination of ______substances as feces

Nutrition

  • Nutrient – substance used by the body for ______, maintenance, and ______
  • Categories of nutrients

1. Carbohydrates

2. ______

3. Proteins

4. Vitamins

5. ______

6. ______

Dietary Sources of Major Nutrients

1. Carbohydrates

  • Most are derived from ______
  • Exceptions: ______from milk and small amounts of glycogens from meats

2. Lipids

  • Saturated ______from animal products
  • Unsaturated fats from ______, ______, and vegetable oils
  • Cholesterol from ______, meats, and milk products

3. Proteins

  • Complete proteins – contain all ______
  • Most are from ______
  • Legumes and ______also have proteins, but are ______

4. Vitamins

  • Most vitamins are used as ______and act with ______
  • Found in all major food groups

5. Minerals

  • Play ______in the body
  • Most mineral-rich foods are ______, legumes, ______, and some ______
  • Water

Metabolism

  • Metabolism – Chemical ______necessary to maintain life
  • Catabolism – substances are ______down to ______substances
  • Anabolism – larger molecules are ______from ______ones
  • Energy is ______during catabolism

Developmental Aspects of the Digestive System

  • Teething begins around age ______
  • Metabolism ______with old age
  • Middle age digestive problems
  • ______
  • Gall bladder problems
  • Activity of digestive tract in old age
  • Fewer digestive ______
  • ______slows
  • Diverticulosis and ______are more common