click below
click below
Normal Size Small Size show me how
ap marieb ch23 pt1
Anat and phys Marieb chap 23 digestive system part 1
Question | Answer |
---|---|
Name two groups of digestive organs | Alimentary and accessory |
Name function of alimentary canal | digests and absorbs food |
Name parts of alimentary canal | oral cavity, pharynx, esophagus, stomach, small intestine, and large intestine |
Name parts of accessory organs | Teeth, tongue, gallbladder Digestive glands -Salivary glands,Liver,pancreas |
Six essential activities of the digestive processes | 1. Ingestion 2. Propulsion 3. Mechanical digestion 4. Chemical digestion 5. Absorption 6. Defecation |
Name four GI tract regulatory mechanisms | Mechanoreceptors and chemoreceptors Intrinsic and extrinsic controls |
Functions of mechanoreceptors and chemoreceptors | Respond to stretch, changes in osmolarity and pH, and presence of substrate and end products of digestion Initiate reflexes that activate or inhibit digestive glands stimulate smooth muscle to mix and move lumen contents |
Functions of Intrinsic and extrinsic controls | Enteric nerve plexuses (gut brain) initiate short reflexes in response to stimuli in the GI tract Long reflexes in response to stimuli inside or outside the GI tract involve CNS centers and autonomic nerves |
Enteric nerve plexuses (gut brain) initiate _______ in response to stimuli in the GI tract | short reflexes |
Long reflexes respond to ________ and involve the ______ and _____ | stimuli inside or outside the GI tract CNS centers and Autonomic nerves |
________ peritoneum on external surface of most digestive organs | Visceral |
________ peritoneum lines the body wall | Parietal |
__________ is between the two peritoneums and lubricates mobile organs | Peritoneal cavity |
_________ is a double layer of peritoneum | Mesentery |
Funtions of mesentery | Routes for blood vessels, lymphatics, and nerves Holds organs in place and stores fat |
________ organs lie posterior to the peritoneum | Retroperitoneal |
__________ organs are surrounded by the peritoneum | Intraperitoneal |
Four basic layers (tunics) of alimentary canal | Mucosa Submucosa Muscularis externa Serosa |
Layers of alimentary canal from inside out | lumen, mucosa( epithelium, lamina propia, muscularis mucosa), submucosa, muscularis externa (circular and longitudinal), serosa (connective tissue and epithelium), mysentery |
Mucosa Functions | Secretes mucus, digestive enzymes and hormones Absorbs end products of digestion Protects against infectious disease |
Three sublayers of mucosa | epithelium, lamina propria, and muscularis mucosae |
Mucosa Epithelium | Simple columnar epithelium and mucus-secreting cells which protects digestive organs from enzymes, eases food passage. May secrete enzymes and hormones |
Mucosa Lamina propria | Loose areolar connective tissue, capillaries for nourishment and absorption, lymphoid follicles (part of MALT) |
Muscularis mucosae | smooth muscle that produces local movements of mucosa |
Submucosa | Dense connective tissue Blood and lymphatic vessels, lymphoid follicles, and submucosal nerve plexus |
Muscularis externa | Responsible for segmentation and peristalsis Inner circular and outer longitudinal layers |
Serosa around organs | Visceral peritoneum |
Visceral peritoneum is replaced by the _____ in the esophagus | fibrous adventitia |
Retroperitoneal organs have both an ____ and ______ | adventitia and serosa |
Intrinsic nerve supply of the alimentary canal is composed of the ____ and the ______ | Submucosal nerve plexus and Myenteric nerve plexus |
Function of the submucosal nerve plexus | Regulates glands and smooth muscle in the mucosa |
Function of the myenteric nerve plexus | Controls GI tract motility |
The Enteric Nervous System is linked to the CNS via ____ ____ ____ | afferent visceral fibers |
____ ANS fibers synapse with enteric plexuses | Long |
________ impulses inhibit secretion and motility in the enteric nervous system | Sympathetic |
_______ impulses stimulate the mouth in the enteric nervous system | Parasympathetic |
The mouth is lined with _____ | stratified squamous epithelium |
The soft palate is formed mostly of ______ | skeletal muscle |
The soft palate closes off the _____ during swallowing | nasopharynx |
Functions of the tongue include | Repositioning and mixing food during chewing, formation of the bolus, initiation of swallowing, speech, and taste |
____ muscles change the shape of the tongue | Intrinsic |
_____ muscles alter the tongue’s position | Extrinsic |
Surfaces of tongue | filiform fungiform circumvallate foliate terminal sulcus |
Filiform | whitish, give the tongue roughness and provide friction |
Fungiform | reddish, scattered over the tongue |
Circumvallate (vallate) | V-shaped row in back of tongue |
These three house taste buds | filiform fungiform circumvallate |
Where are the foliate | on the lateral aspects of the posterior tongue |
Terminal sulcus marks the division between_____ | circumvallate and linguinal tonsil |
3 Extrinsic Salivary Glands | parotid, submandibular, and sublingual |
Saliva secretion function | Cleanses the mouth Moistens and dissolves food chemicals Aids in bolus formation Contains enzymes that begin the breakdown of starch |
_____ salivary glands continuously keep the mouth moist | Intrinsic |
______ salivary glands produce secretions when ingested food stimulates chemoreceptors and mechanoreceptors in the mouth | Extrinsic |
Salivatory nuclei in the brain stem send impulses along _____ fibers in cranial nerves VII and IX | parasympathetic |
Strong ____ stimulation inhibits salivation and results in dry mouth (xerostomia) | sympathetic |
___ deciduous teeth erupt (6–24 months of age) | 20 |
__ permanent teeth | 32 |
4 Classes of Teeth | Incisors, Canines, Premolars (bicuspids) and molars |
Translate this dental formula - 2I,1C, 2PM, 3M | 2 incisors 2 premolars 3 molars |
Parts of Tooth Structure | crown, root, cementum, periodontal ligament, gingival sulcus, dentin, pulp cavity, pul, root canal |
Crown | Exposed part above gum |
Root | Portion embedded in the jawbone and connected to crown by neck |
Cementum | Calcified connective tissue |
Periodontal ligament | Forms fibrous joint |
Gingival sulcus | Groove where gingiva borders the tooth |
Dentin | Bonelike material under enamel |
Pulp cavity | Cavity surrounded by dentin |
Pulp | Connective tissue, blood vessels, and nerves |
Root canal | Extends from pulp cavity to the apical foramen of the root |
Adventitia | outermost layers or covering of some organs |
Bolus | round mass of food prepared by mouth for swallowing |
Deglutition | swallowing |