Digestive system study review

Initial organ of Alimentary Canal…

Initial organ of Alimentary Canal…

Mouth

Enzyme that breaks down starch...

Amylase

Salivary glands situated anterior to the ear...

Parotid Glands

Purpose of Mastication...

Chew, Grind and tear food into small pieces

Anchors tongue

to floor of mouth

Limits movement

Lingual Frenulum

Protein digestion

starts here…

Stomach

Active protein digesting enzyme that HCl is needed

Pepsin

Large wrinkled folds in the stomach lining

Rugae

Produced in stomach needed for vitamin B12 absorption in S.I.

Intrinsic Factor

What sphincter when weakened can cause heartburn

Cardioesophageal Sphincter

Subdivisions of the small intestine

Duodenum, Jejunum, Ileum

Finger like projections; increase absorptive surface

villi

Deep Folds of the mucosa and submucosa

Circular folds (plicae circulares)

Controls food movement from stomach to small intestine

Pyloric

Organs that release secretions into the Duodenum

Liver, Gallbladder, Pancreas

Responsible for water absorption and excretion of feces

Large Intestine

The appendix is attached to the…

Cecum

From the outermost to the innermost layer

Serosa, Muscularis externa, Submucosa, Mucosa

These are numerous in the large intestine and produce alkaline (bicarbonate-rich) mucus

Goblet Cells

Three parts of the large intestine that lie within the pelvic region

Sigmoid Colon, rectum, anal canal

Placement of food into the mouth

Ingestion

Elimination of indigestible particles as feces

Defecation

Enzymes hydrolyze food to their building blocks

Digestion

Transport of products from lumen to the blood or lymph

Absorption

Peristalsis moves food from one organ to the next

Propulsion

Sphincter that operates under voluntary control

External Anal Sphincter

predict the effect on digestion if the pancreas is unable to make and release pancreatic juices. Explain your prediction.

pancreatic juices contain lots of enzymes and bicarbonates. Without the juices the starch digestion will not take full effect, protein digestion will not be fully complete, fat digestion will not be occuring, as well as nucleic acid digestion. Without this happening enzyme activity will not take place and you will likely be severly malnutritionized.

Discuss why an acidic pH is necessary for the stomach's activities to be accomplished.

hydrochloric acid makes the stomach contents acidic. Acid is necessary for the start up of pepsinogen into pepsin. Since pepsin is the active protein-digesting enzyme that begins protein digestion in the stomach. Without it the acidic environment and half of the digestion process for proteins would not be able to occur.

name the 4 layers of the digestive tract from the lumen outwards

mucosa,submucosa,muscularis,and serosa.