BIOL 253 Exam 4 UPDATED ACTUAL
Exam Questions and CORRECT Answers
circular folds - CORRECT ANSWER - deep folds of the mucosa and submucosa that
extend completely or partially around the circumference of the small intestine
covered with fingerlike projections called villi
microvilli - CORRECT ANSWER - projections that increase the cell's surface area
collectively known as a brush border
goblet cells - CORRECT ANSWER - secrete mucus that lubricates and protects the inner
surface of the wall of the small intestine
total surface area of small intestine - CORRECT ANSWER - 250-300 square meters
increased surface area maximizes its absorptive capacity
lacteal - CORRECT ANSWER - single, blind-ended lymphatic vessel
occupies the center of each intestinal villus
most of the fat absorbed in the small intestine enters the lacteals
three segments of the small intestine - CORRECT ANSWER - duodenum (short), jejunum,
ileum (longest)
,most of the chyme that enters the stomach is digested and absorbed in the _____ - CORRECT
ANSWER - duodenum and part of the jejunum
removal of parts of small intestine - CORRECT ANSWER - does not necessarily result in
nutritional deficiencies, depending on which part of the intestine is removed
the remaining tissue can increase its digestive and absorptive capacities to compensate for the
removal of the diseased part
pancreas - CORRECT ANSWER - elongated gland located behind the stomach
produce secretions essential to the function of the small intestine
pancreatic duct - CORRECT ANSWER - delivers exocrine secretions to the duodenum
liver - CORRECT ANSWER - large organ located in upper-right portion of abdomen
secretes bile into small ducts that join to form the common hepatic duct
gallbladder - CORRECT ANSWER - stores secreted bile
small sac underneath the liver that branches from the common hepatic duct
during a meal, smooth muscles in the gallbladder wall are stimulated to contract, causing a
concentrated bile solution to flow down the common bile duct and be injected through the
sphincter of Oddi into the duodenum
secretion into the lumen - CORRECT ANSWER - intestinal epithelium at the base of the
villi secretes a number of mineral ions (Na+, Cl_, HCO3-) into the lumen and water follows by
osmosis
, osmotic gradient is enhanced when chyme entering the small intestine from the stomach is
hypertonic due to high concentrations of solutes resulting from the breakdown of large food
molecules into many more small molecules
pancreatic secretions - CORRECT ANSWER - exocrine portion of pancreas secretes
HCO3 and a number of digestive enzymes into the duodenum
HCO3 is secreted by the epithelial cells lining the pancreatic duct (apical membrane cl-/hco3-
exchanger)
acini - CORRECT ANSWER - lobules at the end of the pancreatic duct system that secrete
the digestive enzymes from the pancreas
cystic fibrosis - CORRECT ANSWER - result in decreased pancreatic hco3- secretion
Enterokinase - CORRECT ANSWER - proteolytic enzyme that converts trypsinogen to
trypsin
embedded in the apical plasma membranes of intestinal epithelial cells
trypsin - CORRECT ANSWER - Proteolytic enzyme that activates other pancreatic
zymogens by splitting off peptide fragments
hepatic lobule - CORRECT ANSWER - functional unit of the liver
portal triad - CORRECT ANSWER - composed of branches of the bile duct, hepatic and
portal veins, and the hepatic artery
where do substances absorbed from the small intestine end up? - CORRECT ANSWER -
1. hepatic sinusoid either to reach the vena cava via the central vein
Exam Questions and CORRECT Answers
circular folds - CORRECT ANSWER - deep folds of the mucosa and submucosa that
extend completely or partially around the circumference of the small intestine
covered with fingerlike projections called villi
microvilli - CORRECT ANSWER - projections that increase the cell's surface area
collectively known as a brush border
goblet cells - CORRECT ANSWER - secrete mucus that lubricates and protects the inner
surface of the wall of the small intestine
total surface area of small intestine - CORRECT ANSWER - 250-300 square meters
increased surface area maximizes its absorptive capacity
lacteal - CORRECT ANSWER - single, blind-ended lymphatic vessel
occupies the center of each intestinal villus
most of the fat absorbed in the small intestine enters the lacteals
three segments of the small intestine - CORRECT ANSWER - duodenum (short), jejunum,
ileum (longest)
,most of the chyme that enters the stomach is digested and absorbed in the _____ - CORRECT
ANSWER - duodenum and part of the jejunum
removal of parts of small intestine - CORRECT ANSWER - does not necessarily result in
nutritional deficiencies, depending on which part of the intestine is removed
the remaining tissue can increase its digestive and absorptive capacities to compensate for the
removal of the diseased part
pancreas - CORRECT ANSWER - elongated gland located behind the stomach
produce secretions essential to the function of the small intestine
pancreatic duct - CORRECT ANSWER - delivers exocrine secretions to the duodenum
liver - CORRECT ANSWER - large organ located in upper-right portion of abdomen
secretes bile into small ducts that join to form the common hepatic duct
gallbladder - CORRECT ANSWER - stores secreted bile
small sac underneath the liver that branches from the common hepatic duct
during a meal, smooth muscles in the gallbladder wall are stimulated to contract, causing a
concentrated bile solution to flow down the common bile duct and be injected through the
sphincter of Oddi into the duodenum
secretion into the lumen - CORRECT ANSWER - intestinal epithelium at the base of the
villi secretes a number of mineral ions (Na+, Cl_, HCO3-) into the lumen and water follows by
osmosis
, osmotic gradient is enhanced when chyme entering the small intestine from the stomach is
hypertonic due to high concentrations of solutes resulting from the breakdown of large food
molecules into many more small molecules
pancreatic secretions - CORRECT ANSWER - exocrine portion of pancreas secretes
HCO3 and a number of digestive enzymes into the duodenum
HCO3 is secreted by the epithelial cells lining the pancreatic duct (apical membrane cl-/hco3-
exchanger)
acini - CORRECT ANSWER - lobules at the end of the pancreatic duct system that secrete
the digestive enzymes from the pancreas
cystic fibrosis - CORRECT ANSWER - result in decreased pancreatic hco3- secretion
Enterokinase - CORRECT ANSWER - proteolytic enzyme that converts trypsinogen to
trypsin
embedded in the apical plasma membranes of intestinal epithelial cells
trypsin - CORRECT ANSWER - Proteolytic enzyme that activates other pancreatic
zymogens by splitting off peptide fragments
hepatic lobule - CORRECT ANSWER - functional unit of the liver
portal triad - CORRECT ANSWER - composed of branches of the bile duct, hepatic and
portal veins, and the hepatic artery
where do substances absorbed from the small intestine end up? - CORRECT ANSWER -
1. hepatic sinusoid either to reach the vena cava via the central vein
