lab 15 (photo)

Serosa

Simple squamous epithlium + areolar CT

Muscular layer/muscularis

Circular and longitudinal smooth muscle

Submucosa

Areolar CT, blood vessels, lymph vessels

Mucosa

Muscularis mucosae, lamina propria, mucous membrane

Muscularis Mucosae

Elastic fibers + circular + longitudinal smooth muscle

Lamina Propria

Areolar CT, blood vessels, lymph vessels and nodules

Mucous membrane

Layer of epithelium, CT + muscle

Hard palate

Bony

forms root of oral cavity + plays an important role in swallowing

Soft palate

Muscular

forms root of oral cavity + plays an important role in swallowing

Uvula

secretes saliva to keep your throat moist + lubricated

Tongue

Pushes food around when you eat + mixes it w/ saliva to form food bolus

Lingual frenulum

Involved in mechanical digestion, attaches tongue to floor of mouth

Teeth

incisors, canines, premolars, molars

Incisors

involved in mechanical digestion, grind food b4 swallowed

Canines

involved in mechanical digestion, grind food b4 swallowed

Premolars

involved in mechanical digestion, grind food b4 swallowed

Molars

involved in mechanical digestion, grind food b4 swallowed

Gingiva (gums)

holds teeth in place, serves as a protective barrier against harmful bacteria

Salivary glands

Parotid, sublingual, submandibular

Parotid gland

Secretes salivary amylase

Secretes mucous + salivary amylase which starts chemical digestion in mouth

Sublingual gland

Mucous

Secretes mucous + salivary amylase which starts chemical digestion in mouth

Submandibular gland

Salivary amylase + mucous

Secretes mucous + salivary amylase which starts chemical digestion in mouth

Pharynx

Oropharynx, laryngopharynx, nasopharynx

Oropharynx

passageway for food + liquid to enter the esophagus; pushes food bolus → esophagus

Laryngopharynx

passageway for food + liquid to enter the esophagus; pushes food bolus → esophagus

Nasopharynx

functions only in respiration (b/c passageway b/w nose + pharynx)

passageway for food + liquid to enter the esophagus; pushes food bolus → esophagus

Esophagus

upper esophogeal sphincter, lower esophogeal sphincter

Upper esophageal sphincter

superior end; skeletal muscle of musularis layer → voluntary

conducts food from laryngopharynx → stomach by peristalsis

Lower esophageal sphincter

lower 3rd; smooth muscle → involuntary

conducts food from laryngopharynx → stomach by peristalsis

Salivary gland

Stomach

Cardia, fundus, body, pylorus, lesser curvature, greater curvature

Cardia

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Fundus

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Body

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Pylorus

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Lesser curvature

Concave side

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Greater curvature

Convex side

Serves as temporary holding area for food + is site for chemical + mechanical breakdown for food

Gastric folds of mucosa (rugae)

Creates extensive stretching to accommodate incoming food

Lesser omentum

Pathway for blood vessels entering the liver + connects stomach to duodenum + liver

Greater omentum

Covers folds of small intestine; contains adipose tissue + lymph nodes

Pyloric sphincter

opens to allow passage of chyme into duodenum of small intestine

Stomach

Stomach epithelium

Pancreatic acini + islets

Pancreas

accessory duct, pancreatic duct

Accessory duct

empties directly into duodenum

accessory digestive organ; releases secretions enzymes into duodenum of small intestine

Pancreatic duct

Joins bile duct to form hepatopancreatic ampulla

accessory digestive organ; releases secretions enzymes into duodenum of small intestine

Liver

Left + Right + common hapatic duct,

Left haptic duct

Stores + convert excess nutrients from blood to correct deficiencies + excretes bile from hepatocytes → cystic ducts of gallbladder converged by common hepatic duct

Right hepatic duct

Stores + convert excess nutrients from blood to correct deficiencies + exertes bile from hepatocytes → cystic ducts of gallbladder converged by common hepatic duct

Common hepatic duct

Left + right converged

Stores + convert excess nutrients from blood to correct deficiencies + exertes bile from hepatocytes → cystic ducts of gallbladder converged by common hepatic duct

Gall bladder

stores bile until needed for digestion

Cystic duct

allows bile to flow in the gallbladder, unites w/ common heptatic duct to form common bile duct

Common bile duct

joins pancreatic duct at hepatopancreatic ampulla where bile can be secereted

hepatopancreatic ampulla

acts as reservoir for pancreatic juices + bile + empties into duodenum of small small intrestine at the major duodenal papilla

Major duodenal papilla

acts as reservoir for pancreatic juices + bile + empties into duodenum of small small intrestine at the major duodenal papilla

Duodenum

Jejunum

Produces digestive juices + enzymes to bread down food + empties it inot the large intestine, also absorbs nutrients

Ileum

Produces digestive juices + enzymes to bread down food + empties it inot the large intestine, also absorbs nutrients

Ileal orifice (ileocecal sphincter)

regulates entery of chyme → large intestine from small intestine

Mesentery

Binds jejunum + ileum to the posterior abdominal wall

Circular folds

Increases SA to absorb nutrients in the small intestine

Duodenum microscope

Cecnum

opens into the colon + moves chyme from small → large intestine

Vermiform appendix

Contains an aggregation of lymphatic nodules; has immune + lymphatic functions

Colon

Ascending, transverse, descending, sigmoid

Ascending Colon

Responsible for formation + expulsion of focus + reabsorbs water + ions

Transverse Colon

Responsible for formation + expulsion of focus + reabsorbs water + ions

Descending Colon

Responsible for formation + expulsion of focus + reabsorbs water + ions

Sigmoid colon

Responsible for formation + expulsion of focus + reabsorbs water + ions

Rectum

end of the Gl tract; stores feces util they can be eliminated

Anus

Internal anal sphicter, external anal sphinceter

Internal anal sphincter

expels feces from body; takes part in defecation through relaxation of the sphincters

External anal sphincter

Voluntarily controlled to allow/postpone defecation

expels feces from body; takes part in defecation through relaxation of the sphincters

Mesocolon

binds transverse + sigmoid colons to posterior abdominal wall

Teniae coli

longitudinal muscle bands that causes pouches to form in the colon → haustrae

Haustrae

pouches of colon in which walls contract to squeeze the digested contents → next hastrum

Large intestine

Salivary Gland

Has Mucous acini + serous acini

Mucous acini

secretes mucous, lubricates mouth to protect teeth + helps w/ swallowing

Serous acini

secretes serous fluid, liquid hydrolysis + taste

Stomach

Chief cells, G cells, Parietal cells, Mucous cells

Chief cells

Secretes pepsinogen, activates into pepsin; turns proteins → peptides

G cells

Secretes gastrin, stimulates additional secretions of gastric juices when food arrives in the stomach

Parietal cells (hydrochloric acid)

Secretes hydrochloric acid, activates pepsinogen → pepsin for enzymatic digestion

Parietal cells (intrinsic factor)

Secretes intrinsic factor, necessary for absorption of vitamin B12 in the ileum of small intestine

Pancreas

Trypsinogen, pancreatic lipase, pancreatic amylase, sodium bicarbonate

Trypsinogen

Breaks down peptide bonds in certain a.a (digestion of protein)

Pancreatic lipase

digests triglycerides (monoglycerides + fatty acids)

Pancreatic amylase

Splits polysacharides → oligosccharides

Sodium bicarbonate

Converts acid chyme to an alkaline pH

Liver

Hepatocytes

Hepatocytes

Secrete bile, emulsifies fat to help absorption of lipids

Small intestine

Goblet cells, duodenal glands, intestinal glands

Goblet cells (large)

Secrete mucus, protects lining of small intestine

Duodenal glands

secrete alkaline mucus, neutralizes acid chyme

Intestinal glands

secretes intenstinal juice, provides a liquid medium to aid for absorption

Large intestine

Goblet cells

Goblet cells (small)

secretes mucus, lubricates intesntine to facilitate passage of fecal material

List the structures (or parts of structures) involved in mechanical digestion.

Teeth, tongue, stomach, small + large intestine