Question | Answer |
Functions of Digestive Sys | Digests food and absorbs products |
6 activities of system | Ingestion, mechanical digestion, propulsion, chemical digestion, absorption, defecation |
2 types of movement and definitions | peristalsis (pushes food) and segmentation (alternating bands of contraction that MIX food) |
Functions of salivary glands | cleanse the mouth, moisten/dissolve food, aid in formation of bolus, start chem digestion |
Number of teeth (deciduous and perm) | 20 and 32 |
3 types of salivary glands | parotid, sublignual, submandibular |
layers of muscle in stomach | longitudinal, circular, oblique |
Types of secretory cells in stomach | mucous, parietal, chief |
Function of mucous cells | secrete mucus |
function of parietal cells | secrete HCl and intrinsic factor (necessary to absorb B12) |
function of chief cells | secretes pepsinogen |
Phases of gastric secretion | cephalic, gastric, intestinal |
Cephalic Phase (excitatory/inhibitory events) | excit: sight/thought of food stimulates smell and taste receptors inhib: loss of appetitie, depression, decrease in PNS |
Purpose of cephalic phase | prepare stomach for digestion |
Gastric Phase (excitatory/inhibitory events) | excit: stretching stomach, activate chemoreceptors (inc pH, peptides) inhib: pH<2 or emotional upset that overrides PNS |
Chemicals released during Gastric Phase | Gastrin (from parietal cells), ACh (for production of more gastric juice), Histamine |
Intestinal Phase (excitatory/inhibitory events) | excit: low pH inhib: fatty, acidic, hypertonic chyme and stretching |
Define Plicae Circularis | circular folds that move food through sm. intesting in a corkscrew manner with villi |
Function of segmentation | brings food in to contact with wall of small intestine |
Function of villi | increase surface area of capillary beds |
Function of Lg. intestine | absorb H20 and water-soluble vitamins -NOT vital for life |
Define teniae coli | bands of longitudinal muscle |
Define Vermiform appendix | structure off of cecum with a small immune role |
Order of Chemical digestion for Carbs | Startsin mouth with salivary amylase, moves to stomach where amylase deactivates, moves to pancreatic amylase, transported into cap bed of sm. intestine, then to liver via hepatic portal system |
Pepsin | cleaves bonds of amino acids and digests proteins in stomach |
3 substances produced by sm. int for protein digestion | Trypsin, Chymotripsin, Carboxypeptidase (splits at carboxy end) |