A&P_Unit_1_Review - Review for unit 1 Review for...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Review for unit 1 Review for chapter 23: 1. Identify the parts of digestive system: digestive organs and the accessory organs of alimentary canal and label them. Digestive organs of the alimentary canal: mouth, pharynx, esophagus, stomach, small intestine, and large intestine. Accessory digestive organs: teeth, tongue, gallbladder, and a number of large digestive glands—salivary glands, liver, and pancreas. See Fig 23.1 page 883. 2. What are the different digestive processes? familiarize with Fig 23.2. 1. ingestion —taking food into the digestive tract, usually via the mouth 2. propulsion —moves food through the alimentary canal, includes swallowing (which is voluntary), and peristalsis (involuntary) 3. mechanical digestion —physically prepares food for chemical digestion by enzymes; includes chewing, mixing of food with saliva and by the tongue, churning food in the stomach, and segmentation 4. chemical digestion —a series of catabolic steps in which complex food molecules are broken down to their chemical building blocks by enzymes secreted into the lumen of the alimentary canal 5. absorption —the passage of digested end products (plus vitamins, minerals, and water) from the lumen of the GI tract through the mucosal cells by active or passive transport into the blood or lymph (small intestine is the major absorptive site) 6. defecation —eliminates indigestible substances form the body via the anus in the form of feces 7. What are peristalsis and segmentation? Peristalsis —involves alternate waves of contraction and relaxation of muscles in the organ walls (it is the major means of propulsion), its main effect is to squeeze food along the tract, but some mixing occurs as well; it moves in ONE direction. Segmentation —rhythmic local constrictions of the intestine; it mixes food with digestive juices and increases the efficiency of absorption by repeatedly moving different parts of the food mass over the intestinal walls; it allows the food to mix by going back and forth. 3. What are long and short nerve controls? Short reflexes —mediated entirely by the local plexuses in response to the GI tract stimuli; long reflexes —initiated by stimuli arising inside or outside the GI tract and involve CNS centers and extrinsic autonomic nerves. See Fig 23.4 page 885. 4. What is visceral peritoneum,? mesentery? retroperitoneal and intraperitoneal organs? Digestive organs are covered by two layered peritoneum. The layer close to the organs are called visceral peritoneum , the one adjacent to the body wall is called parietal peritoneum. Some organs (like the stomach) have two layers of serous membranes fused to each other and extend the organ to the body wall, called mesentery . It is mostly dorsal, but can be ventral. These organs are called peritoneal or
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 9

A&P_Unit_1_Review - Review for unit 1 Review for...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online