Chap 24 Flashcards
What is the peritoneum?
The largest cavity, housing abdominal organs, and containing blood and lymphatic vessels.
What is the mesentery?
Holds the intestines in place and contains the most fat.
What are the roles of the omentum?
Fat storage and immune response roles.
What is the function of the falciform ligament?
Anchors the liver to the anterior abdominal wall.
What is mechanical digestion?
Breakdown of food into smaller pieces via chewing, churning, and segmentation.
Where does mechanical digestion occur?
Mouth (chewing/mastication), Stomach (churning), Small intestine (segmentation contractions).
What is chemical digestion?
Breakdown of food molecules into simpler forms via enzymes.
Where does chemical digestion occur?
Mouth (salivary amylase for carbohydrates), Stomach (pepsin for proteins), Small intestine (enzymes from pancreas and brush border enzymes for all macromolecules).
What is the mucosa?
Inner layer for secretion and absorption.
What does the submucosa contain?
Blood, lymphatic vessels, and nerves.
What is the function of the muscularis?
Smooth muscle responsible for peristalsis (propulsion of food).
What is the serosa?
Outer layer providing structural support.
What is the function of the upper esophageal sphincter?
Regulates entry of food into the esophagus.
What does the lower esophageal sphincter (LES) prevent?
Prevents reflux of stomach acid into the esophagus.
What does the pyloric sphincter control?
Controls passage of chyme from stomach to small intestine.
What is the function of the ileocecal valve?
Regulates movement of chyme from the small to large intestine.
What do anal sphincters control?
Control defecation.
What is produced by parietal cells in the stomach?
Intrinsic Factor
Intrinsic Factor is essential for vitamin B12 absorption in the small intestine.
What is the term for chewed food mixed with saliva?
Bolus
Bolus is formed in the mouth and travels down the esophagus.
What do we call partially digested food mixed with gastric juices?
Chyme
Chyme is found in the stomach and small intestine.
What is the semi-solid waste after water absorption called?
Feces
Feces are formed in the large intestine.
What hormone is produced in the duodenum and stimulates bile release?
CCK (Cholecystokinin)
CCK also stimulates the pancreas to release digestive enzymes.
What are lacteals?
Lymphatic vessels in the small intestine
Lacteals absorb dietary fats and form chyle, a milky lymph.
What is the function of segmentation contractions in the small intestine?
Mix and churn food to enhance digestion and absorption
Segmentation contractions increase the efficiency of nutrient absorption.
Where is most water reabsorbed in the digestive system?
Small intestine
Additional reabsorption occurs in the large intestine.
What are bile salts and where are they produced?
Produced by the liver, stored in the gallbladder
Bile salts emulsify fats to increase surface area for enzymatic digestion.
What is the function of lipases?
Digest lipids
Lipases are one of the pancreatic products involved in digestion.
What do proteases digest?
Proteins
Proteases are enzymes secreted by the pancreas into the duodenum.
What is the role of bicarbonate buffer in the digestive system?
Neutralizes acidic chyme entering the duodenum
Bicarbonate buffer is produced by the pancreas.
What do High-Density Lipoproteins (HDL) do?
Transport cholesterol to the liver for excretion
HDL is considered beneficial for heart health.
