A&P 2 Lecture (BIOL 2302) Exam 4 Review Questions |
2026/2027 | Answers Correct | With Complete Solutions
Cholecystokinin (CCK)
-causes secretion of pancreatic juice
-causes the hepatopancreatic sphincter to relax
What regulates the process of pancreatic juice secretion?
-cholecystokinin (CCK) induces secretion of enzyme-rich juice
by acini
-Secretin causes secretion of bicarbonate-rich juice by duct cells
-Vagal stimulation also causes release
Digestion in the Small Intestine
-Chyme from stomach contains partially digested carbohydrates
and proteins, & undigested fats
-after 3-6 hours in small intestine, most of the water is absorbed
and almost all nutrients are absorbed
What are the requirements for digestion and absorption in the
small intestine?
-Slow delivery of acidic, hypertonic chyme
-Delivery of bile, enzymes, and bicarbonate ions from liver and
pancreas
-Mixing
Segmentation of the Small Intestine
-Most common motion of small intestine
-Initiated by intrinsic pacemaker cells
,-Mixes & moves contents toward ileocecal valve
-Intensity altered by long & short reflexes, & hormones
-Wanes in late intestinal (fasting) phase
How does parasympathetic nerve stimulation effect
segmentation of the small intestine?
increases it
How does sympathetic nerve stimulation effect segmentation of
the small intestine?
decreases it
Peristalsis of the Small Intestine
-Initiated by rise in hormone motilin in late intestinal phase
-occurs every 90-120 minutes
-Each wave starts distal to previous
-Meal remnants, bacteria, and debris moved to large intestine
-particles travel from the duodenum to the ileum in around 2
hours
Myenteric Plexus
-Causes contraction of circular muscle proximally and of
longitudinal muscle distally
-Forces chyme along tract
-may be activated by cholinergic sensory neurons
What neurons coordinate intestinal motility?
local enteric neurons
When does the ileocecal sphincter relax and admit chyme into
the large intestine?
,-when the gastroileal reflex enhances force of segmentation in
ileum
-when gastrin increases motility of ileum
Ileocecal Valve
flaps close when chyme exerts backward pressure, which
prevents regurgitation into ileum
Teniae Coli of the Large Intestine
Three bands of longitudinal smooth muscle in muscularis
Haustra of the Large Intestine
Pocketlike sacs caused by tone of teniae coli
Epiploic Appendages
Fat-filled pouches of visceral peritoneum
Cecum
first part of large intestine
Appendix
-region of the large intestine
-masses of lymphoid tissue
-Part of MALT of immune system
-Bacterial storehouse that recolonizes the gut when necessary
-Twisted structure
How do particles travel through the different regions of the
colon in order?
1. Ascending colon
2. Right colic (hepatic) flexure
, 3. Transverse colon
4. Left colic (splenic) flexure
5. Descending colon
6. Sigmoid colon
7. Rectum
Rectum
-region of the large intestine
-Three rectal valves stop feces from being passed with gas
Anal Canal
-Last segment of large intestine
-Opens to body exterior at anus
What sphincters are found in the anal canal?
-Internal anal sphincter which is composed of smooth muscle
-External anal sphincter which is composed of skeletal muscle
Bacterial Flora
-Enter from small intestine or anus
-Colonize the colon
-Synthesize B complex vitamins and vitamin K
-Metabolize some host-derived molecules
-Ferment indigestible carbohydrates
-Release irritating acids and gases
Intestinal Flora
-Viruses and protozoans
-Bacteria prevented from breaching mucosal barrier
Digestive Processes in the Large Intestine
2026/2027 | Answers Correct | With Complete Solutions
Cholecystokinin (CCK)
-causes secretion of pancreatic juice
-causes the hepatopancreatic sphincter to relax
What regulates the process of pancreatic juice secretion?
-cholecystokinin (CCK) induces secretion of enzyme-rich juice
by acini
-Secretin causes secretion of bicarbonate-rich juice by duct cells
-Vagal stimulation also causes release
Digestion in the Small Intestine
-Chyme from stomach contains partially digested carbohydrates
and proteins, & undigested fats
-after 3-6 hours in small intestine, most of the water is absorbed
and almost all nutrients are absorbed
What are the requirements for digestion and absorption in the
small intestine?
-Slow delivery of acidic, hypertonic chyme
-Delivery of bile, enzymes, and bicarbonate ions from liver and
pancreas
-Mixing
Segmentation of the Small Intestine
-Most common motion of small intestine
-Initiated by intrinsic pacemaker cells
,-Mixes & moves contents toward ileocecal valve
-Intensity altered by long & short reflexes, & hormones
-Wanes in late intestinal (fasting) phase
How does parasympathetic nerve stimulation effect
segmentation of the small intestine?
increases it
How does sympathetic nerve stimulation effect segmentation of
the small intestine?
decreases it
Peristalsis of the Small Intestine
-Initiated by rise in hormone motilin in late intestinal phase
-occurs every 90-120 minutes
-Each wave starts distal to previous
-Meal remnants, bacteria, and debris moved to large intestine
-particles travel from the duodenum to the ileum in around 2
hours
Myenteric Plexus
-Causes contraction of circular muscle proximally and of
longitudinal muscle distally
-Forces chyme along tract
-may be activated by cholinergic sensory neurons
What neurons coordinate intestinal motility?
local enteric neurons
When does the ileocecal sphincter relax and admit chyme into
the large intestine?
,-when the gastroileal reflex enhances force of segmentation in
ileum
-when gastrin increases motility of ileum
Ileocecal Valve
flaps close when chyme exerts backward pressure, which
prevents regurgitation into ileum
Teniae Coli of the Large Intestine
Three bands of longitudinal smooth muscle in muscularis
Haustra of the Large Intestine
Pocketlike sacs caused by tone of teniae coli
Epiploic Appendages
Fat-filled pouches of visceral peritoneum
Cecum
first part of large intestine
Appendix
-region of the large intestine
-masses of lymphoid tissue
-Part of MALT of immune system
-Bacterial storehouse that recolonizes the gut when necessary
-Twisted structure
How do particles travel through the different regions of the
colon in order?
1. Ascending colon
2. Right colic (hepatic) flexure
, 3. Transverse colon
4. Left colic (splenic) flexure
5. Descending colon
6. Sigmoid colon
7. Rectum
Rectum
-region of the large intestine
-Three rectal valves stop feces from being passed with gas
Anal Canal
-Last segment of large intestine
-Opens to body exterior at anus
What sphincters are found in the anal canal?
-Internal anal sphincter which is composed of smooth muscle
-External anal sphincter which is composed of skeletal muscle
Bacterial Flora
-Enter from small intestine or anus
-Colonize the colon
-Synthesize B complex vitamins and vitamin K
-Metabolize some host-derived molecules
-Ferment indigestible carbohydrates
-Release irritating acids and gases
Intestinal Flora
-Viruses and protozoans
-Bacteria prevented from breaching mucosal barrier
Digestive Processes in the Large Intestine
