lab 10 & 12 Flashcards
digestion of carbohydrates
test 4: add amylase in ice bath 4 mins then add starch
incubate at 37 C
digestion of proteins
test 3: add trypins and heating block for 4 mins
place in ice bath for 1 hr at incubate 37 c
digestion of fats
for test 2: add pancreatin and place in heating bloock 4 mins then add litmus cream
cover n shake and put in ice bath for 1 hr incubate at 37c
What are the main components of the gastrointestinal (GI) tract?
Oral cavity, pharynx, esophagus, stomach, small intestine, large intestine.
What are the accessory organs of the digestive system?
Salivary gland, liver, gall bladder, pancreas.
What are the components of the oral cavity?
Mucus membrane, tongue, teeth, gingivae.
What is the hard palate?
- Anterior portion of the roof of the oral cavity
Hard due to underlying palatine bones and palatine processes of maxillae
What is the soft palate?
- Posterior portion of the roof of the oral cavity
Muscular, with no bone underneath
Rises to close off the nasopharynx when swallowing
What is the superior lip?
Forms the upper portion of the anterior opening into the oral cavity
What is the superior labial frenulum?
Attaches the upper lip to the gums
What are the fauces?
The posterior opening of the oral cavity into the oropharynx
What is the inferior labial frenulum?
Attaches the lower lip to the gums
What is the vestibule in the oral cavity?
The space between the lips, cheeks, and teeth
vestibule
The space between the lips, cheeks, and teeth
What is the function of the cheek in the oral cavity?
Forms the lateral walls of the oral cavity
What is the tongue composed of, and what are its functions?
- Composed of skeletal muscle
Lies in the floor of the oral cavity
Helps mix food, swallow, and produce speech
Location of the majority of taste buds
What is the lingual frenulum?
Attaches the body of the tongue to the floor of the mouth
What is the gingiva?
- Commonly called the gum
Mucous membrane surrounding the base of the teeth
What is the inferior lip?
Forms the lower portion of the anterior opening into the oral cavity
Where are the teeth located?
In the upper and lower jaw
What is the gingivae or teeth
The mucous membrane surrounding the base of the teeth, commonly known as the gums
What is the crown of a tooth?
- The portion of a tooth that is visible
Located above the gum line
What are incisor teeth, and what are they designed for?
- Have a narrow edge, like a knife blade
Designed for cutting and biting
What is a cuspid tooth, and what is it also called?
- Also called an eye tooth or canine tooth
Has a single point
Designed for biting
What are bicuspid teeth, and what are they designed for?
- Have two flat cusps
Designed for grinding
What is the root of a tooth?
- The portion of a tooth that is not visible
Located below the gum line
What is another name for the third molar?
Wisdom tooth
What are molar teeth, and what are they designed for?
- Larger teeth with multiple rounded cusps
Designed for grinding
What is the junction between the crown and root of the tooth called?
Neck
What covers the crown of the tooth?
Enamel
What is harder than bone and covers the crown?
Enamel
What underlies enamel and forms the bulk of the root?
Dentin
What is dentin made of?
Calcified connective tissue
What is the soft tissue surrounding the teeth called?
Gingiva
What is the chamber within the tooth that houses blood vessels and nerves?
Pulp cavity
What covers the root of the tooth?
Cementum
What anchors the tooth in the socket?
Periodontal ligament
What is the section of the pulp cavity found in each root?
Root canal
What is continuous with the pulp cavity and located in each root?
Root canal
What structures are located in the pulp cavity?
Nerves and blood vessels
What are the three parts of the pharynx?
Nasopharynx, Oropharynx, Laryngopharynx
What part of the pharynx is located at the top and connects to the nasal cavity?
Nasopharynx
What part of the pharynx is located in the middle and connects to the mouth?
Oropharynx
What part of the pharynx is located at the bottom and connects to the larynx and esophagus?
Laryngopharynx
What are the lymphoid tissues found in the pharynx called?
Tonsils
What is the serosa in the GI tract?
Serosa is the outermost layer of the GI tract that provides protection and support to the organs.
What is the epithelium in the GI tract?
Epithelium is the tissue layer lining the GI tract, involved in absorption and secretion.
What is the lamina propria in the GI tract?
Lamina propria is a layer of connective tissue beneath the epithelium that supports blood vessels and immune cells.
What is the muscularis mucosae in the GI tract?
Muscularis mucosae is a thin muscle layer .
What is the myenteric plexus in the GI tract?
Myenteric plexus is a network of nerves that controls muscle contractions and motility in the GI tract.
What is the mucosa in the GI tract?
The mucosa is the deepest layer that lines the lumen of the GI tract, also called the mucous membrane, and consists of epithelium, lamina propria, and muscularis mucosae.
What does the submucosa contain in the GI tract?
-dense irregular connective tissue, -submucosal glands (in some regions)
-network of nerves called the submucosal plexus.
What is the muscularis externa in the GI tract made of?
The muscularis externa consists of multiple layers of smooth muscle, with an inner layer of circular fibers and an outer layer of longitudinal fibers. It also contains a network of nerves called the myenteric plexus.
What is the function of the muscularis externa?
The muscularis externa contracts to mix food with digestive juices and propel food through the GI tract.
What is the epithelium like in different parts of the GI tract?
The epithelium is stratified squamous in the esophagus, simple columnar in the stomach and intestines, and keratinized stratified squamous in the anus.
What is the lamina propria made of in the GI tract?
loose connective tissue and contains mucosal glands, especially in the stomach and large intestine. It also contains lymphatic nodules.
What is the muscularis mucosae in the GI tract?
The muscularis mucosae is a thin layer of smooth muscle.
What is the myenteric plexus?
network of nerves located within the muscularis externa that controls GI tract motility.
serosa in the GI tract?
serosa is the outermost layer, a serous membrane that is part of the visceral peritoneum. The esophagus has adventitia instead of serosa.
submucosal glands secrete?
Submucosal glands in the esophagus secrete mucus, and in the duodenum, they secrete buffers and digestive enzymes.
What are villi in the small intestine?
Villi are finger-like extensions of the mucosa in the small intestine that increase surface area for nutrient absorption.
gastric pits and glands in the stomach?
Gastric pits are small depressions in the stomach lining that lead to gastric glands, which secrete digestive enzymes, hydrochloric acid, and mucus.
chyme in the stomach?
Chyme is the partially digested food mixed with stomach acids and enzymes, resulting from the action of stomach contractions.
function of enzymes in the stomach?
Enzymes in the stomach, like pepsin, help break down proteins into smaller peptides as part of digestion.
What are rugae in the stomach?
Rugae are the folds in the stomach lining that allow the stomach to expand when filled with food.
What are the main regions of the stomach?
The main regions of the stomach include the cardia (entrance), fundus (upper part), and pyloric antrum (lower part).
What muscle layers are present in the stomach?
The stomach has three layers of muscle: the inner oblique layer, the middle circular layer, and the outer longitudinal layer.
What role does the stomach play in digestion?
The stomach churns food, mixes it with digestive enzymes and acids, and begins the breakdown of proteins while converting food into chyme.
What is the cardia of the stomach?
The cardia is the region of the stomach that receives food from the esophagus.
What is the fundus of the stomach?
The fundus is the dome-shaped superior region of the stomach that holds food.
What is the pyloric canal?
The pyloric canal is the opening through the pyloric sphincter that connects the stomach to the duodenum.
What is another name for the lower esophageal sphincter?
The lower esophageal sphincter is also called the cardiac sphincter.
What are the layers of the muscularis externa in the stomach?
The muscularis externa consists of the outer longitudinal layer, the middle circular layer, and the inner oblique layer.
What is the body of the stomach?
The body is the largest region of the stomach and is responsible for mixing food with gastric juices.
What is the duodenum?
The duodenum is the first section of the small intestine n recieves chyme from stomach and digestive enzymes
What are rugae in the stomach?
Rugae are folds in the gastric mucosa that flatten out to allow the stomach to expand as it fills with food.
What is the pyloric antrum?
The pyloric antrum is the tapering distal part of the stomach leading to the duodenum.
What is the ileum?
The ileum is the third section of the small intestine. It delivers remaining material to the cecum of the large intestine.
What is the cecum?
The cecum is an expanded pouch that collects material from the ileum and begins compaction.
What is the appendix?
The appendix is a slender, hollow attachment off the distal cecum that contains lymphoid nodules.
What is the sigmoid colon?
The sigmoid colon is the S-shaped section of the large intestine that connects to the rectum.
What is the rectum?
The rectum stores feces prior to defecation and is the distal opening of the GI tract.
What are taenia coli?
Taenia coli are longitudinal bands of smooth muscle in the colon that contract to cause the colon to “pucker” and form haustra.
What are haustra?
Haustra are the series of pouches formed by the muscularis externa in the colon.
Where is the sublingual gland located?
The sublingual gland lies in the floor of the mouth under the tongue.
Where is the parotid gland located?
The parotid gland is the largest salivary gland and lies on the surface of the masseter muscle just distal to the ear.
Where is the submandibular gland located?
The submandibular gland lies in the floor of the mouth along the inner surface of the mandible.
What are the two additional lobes of the liver visible only from the posterior?
The caudate lobe and quadrate lobe are visible only from the posterior.
What is the function of the left lobe of the liver?
The left lobe of the liver performs multiple functions, one of which is to produce bile. Bile emulsifies lipids and fats, making digestion easier.
What is the function of the cystic duct?
The cystic duct connects the gallbladder to the common hepatic duct and common bile duct.
What does the common bile duct do?
The common bile duct conducts bile from the common hepatic duct or cystic duct to the duodenum.
What is the hepatopancreatic ampulla?
The hepatopancreatic ampulla is the point at which the common bile duct and pancreatic duct connect to the duodenum.
What is the function of the pancreatic duct?
The pancreatic duct conducts pancreatic juices to the duodenum.
What are acinar cells in the pancreas?
Acinar cells in the pancreas are exocrine cells that secrete many digestive enzymes and buffers to counteract acidic chyme entering the duodenum from the stomach.
What are pancreatic islets?
Pancreatic islets are clusters of endocrine cells in the pancreas
What is the hepatic portal triad?
The hepatic portal triad is the area between liver lobules that contains the venule of the hepatic portal vein, bile ducts, and a branch of the hepatic artery.
What are acini in the pancreas?
Acini are the exocrine cells in the pancreas that secrete digestive enzymes.
What are the islets of Langerhans in the pancreas?
The islets of Langerhans are clusters of endocrine cells in the pancreas that secrete hormones.
What are pancreatic secretions?
Pancreatic secretions include digestive enzymes and bicarbonate to aid digestion and neutralize stomach acid.
What are pancreatic hormones?
Pancreatic hormones include insulin and glucagon, which regulate blood sugar levels.
What are pancreatic islets
aka called islets of Langerhans)
Pancreatic islets are clusters of endocrine cells in the pancreas that secrete insulin and glucagon.
Pancreatic islets are clusters of endocrine cells in the pancreas that secrete insulin and glucagon.
Acinar cells are exocrine cells in the pancreas that secrete digestive enzymes and buffers.
What is mechanical digestion?
Mechanical digestion is the physical breakdown of food, such as chewing and stomach churning
Where does chemical digestion begin and end?
Chemical digestion starts in the mouth and ends in the small intestine.
What are the main types of carbohydrates involved in digestion?
The main types of carbohydrates are starch, glycogen, maltose, lactose, sucrose, galactose, and fructose.
What are the key components involved in protein digestion?
The key components in protein digestion are pepsin, proteases, peptidases, trypsin, and amino acids.
