ANP 1107 Flashcards
Midterm 1
What are the main functions of the digestive system?
-Ingestion
-Break down into nutrient molecules
-Absorb nutrients into bloodstream
-Rid body of any indigestible remains
-Production of neurotransmitters (gastrin, secretin, CCK, motilin)
-Nutrient production (serotonin)
What are the two groups of organs in the digestive system?
-Alimentary Canal (GI Tract)
-Accessory Digestive Organs/Structures
What is the purpose of the Alimentary Canal (GI Tract)
-Digests and absorbs food through lining (mucosa) into blood
What are the purpose of the accessory digestive organs/structures?
-Mechanical and chemical digestion of food
List the elements of the GI Tract
- Mouth
- Pharynx
- Esophagus
- Stomach
- Small Intestine
- Large Intestine
- Anus
List the elements of the accessory digestive organs/structures
-Teeth
-Tongue
-Gallbladder
-Digestive glands
–Liver
–Pancreas
–Salivary Glands
What are the major digestive processes
- Ingestion
- Mechanical Breakdown
- Propulsion
-Swallowing
-Peristalsis - Digestion
-Catabolism - Absorption
- Compaction & Defecation
What is Peristalsis?
-Adjacent segments of alimentary tract organs alternately contract and relax
-Some mixing may occur
-Food is moved forward
What is Segmentation?
-Nonadjacent segments of alimentary tract organs alternately contract and relax
-Food mixing & breakdown; slow food propulsion occurs
-Food is moved forward and backward
What is the difference between visceral peritoneum and parietal peritoneum?
-Visceral peritoneum is the lining that covers individual digestive organs within the abdominal cavity, while the parietal peritoneum lines the outer body wall.
What is peritonitis?
The inflammation and swelling of the peritoneum.
What does mesentery mean?
-It is a double layer of peritoneum, which is fused together and extends to the organs from the body wall mostly posterior
-Provides support for the organs; holds them in place
-Stores fat
What does intraperitoneal mean?
-Organs that are located within the peritoneum
What does retroperitoneal mean?
-Organs located outside/posterior to the peritoneum
-I.e. most of pancreas, some of the large intestine, duodenum
Name the four basic layers that all digestive organs have
-Mucosa
-Submucosa
-Muscularis externa
-Serosa
Name the three functions of the Mucosa?
- Secretion: mucus, digestive enzymes, hormonmes
- Absorption: end products of digestion
- Protection: against infectious disease
What are the three sublayers of the Mucosa?
- Epithelium - Simple columnar epithelium rich in mucus-secreting cells (Goblet cells)
- Lamina propria - Loose areolar CT: capillaries for nourishment & absorption
- Muscularis mucosae - smooth muscle that produces local movements of mucosa
What are the functions/traits of the Submucosa?
-Areolar CT
-Blood and lymphatic vessels, lymphoid follicle
-Submucosal nerve plexus
-Abundant in elastic fibres
What are the functions/traits of the Muscularis externa?
-Segmentation & Peristalsis
-Inner circular & outer longitudinal layers
-Sphincters in organ-to organ junctions
-Myenteric nerve plexus
What are the functions/traits of the Serosa?
-Visceral peritoneum: outermost protective layer
-Areolar connective tissue covered with mesothelium
-Replaced by the fibrous adventitia in the esophagus (adventitia: fibrous connective tissue that “binds” the esophagus to surrounding tissues)
