Question | Answer |
6 steps of the process of digestion (1-3) | 1. ingestion: taking food into the digestive track
2. propulsion: food moves through alimentary canal. includes swallowing and peristalsis. waves of contraction and relaxation.
3. mechanical digestion: food is prepared for chem digestion |
6 steps of the process of digestion (4-6) | 4. chemical digestion: complex food particles broken down by enzymes
5. absorption: end products move from lumen through mucosal cells
6. defication: eliminates indigestable substances from body |
Peristalsis | Progressive, wavelike contractions that move foodstuffs through the alimentary canal |
Mesentary | Double layered extensions of the peritoneum that support most organs in the abdominal cavity |
Mouth | begins digestive process-- lips, cheeks, palate, uvula, palatoglossal arches, platopharangeal arches, fauces, tongue. |
Bolus | A rounded mass of food prepared by the mouth for swallowing |
Teeth | Incisors (8)-- cut/nip of pieces of food. Canines (4)-- tear, pierce. Premolars/Bicuspids (8)and Molars (12)-- grind, crush |
Pharynx | Involved in swallowing. the passage way that both air and foods are passed through |
Esophagus | Passageway to stomach. |
Mastication | Process of mechanically breaking down food. |
Chyme | Semi-fluid paste of food and gastric juice |
Stomach | Mixes food with gastric juice, initiates protein digestion, absorbs some nutrients. located in the upper left portion of abdominal cavity |
Rugae | Folds of the inner mucous membrane of organs, such as the stomach, that allow those organs to expand. |
Pepsin | A digestive enzyme that chemically digests, or breaks down, proteins into shorter chains of amino acids |
Hydrochloric acid | Helps turn the solid food into a liquid that makes digestion possible |
Intrinsic factor | a substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12 |
Small intestine | Completes digestion of chyme, absorbs nutrients, transports waste to large intestine.
1. duodenum (first 25cm), 2. jejunum, 3. ileum |
Villi and Microvilli | Microscopic projections which cover the intestine, greatly increasing the surface area and therefore, increasing the ability to absorb nutrients |
Liver | Carb, lipid, and protein metabolism. stores gycogen, iron, vitamins a d and b12 |
Gallbladder | Stores bile which breaks down fat globules and enhances absorption of lipids and vitamins a d e and k |
Bile salts | Absorbed as whole molecules at the far end of the small intestine and pass up the portal vein to the liver, when they are re-secreted into bile. |
Pancreas | Secretes juices into the duodenum that contain enzymes that break down carbs, fats, proteins and nucleic acids. |
Large intestine | 1. ascending colon, 2. transverse colon, 3. descending colon, 4. sigmoid colon, 5. rectum. |