click below
click below
Normal Size Small Size show me how
ch 24 - bio169
digestive system
| Question | Answer |
|---|---|
| Ingestion | occurs when materials enter the digestive tract via the mouth. |
| Mechanical Processing | crushing and shearing that makes materials easier to propel along the digestive tract |
| Digestion | the chemical breakdown of food into small organic fragments suitable for absorption by the digestive epithelium. |
| Secretion | the release of water, acids, enzymes, buffers, and salts by the epithelium of the digestive tract and by glandular organs. |
| Absorption | the movement of organic substrates, electrolytes, vitamins, and water across the digestive epithelium and into the interstitial fluid of the digestive tract. |
| Excretion | the removal of waste products from body fluids. |
| The lining of the digestive tract plays a protective role by safeguarding surrounding tissues against: | 1. The corrosive effects of digestive acids and enzymes 2. Mechanical stresses, such as abrasion 3. Bacteria that either are swallowed with food or reside in digestive tract. |
| Visceral Peritoneum | covers organs within the peritoneal cavity |
| Parietal Peritoneum | lines the inner surfaces of the body wall |
| Mesentery | double sheets of peritoneal membrane |
| Lesser omentum | stabilizes the position of the stomach and provides an access route for blood vessels and other structures entering or leaving the liver |
| Falciform Ligament | helps stabilize the position of the liver relative to the diaphragm and abdominal wall |
| The major layers of the digestive tract: | 1. Mucosa 2. Submucosa 3. Muscularis externa 4. Serosa |
| Mucosa | Inner lining of the digestive tract |
| Enteroendocrine Cells | secretes hormones that coordinate the activities of the digestive tract and the accessory glands. |