26.3 Lower Gastrointestinal Tract and Associated Accessory Digestive Organs

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What symptoms may an individual with faltering liver function experience?

Fatigue, weight loss, and nausea (correct)

Fatigue, weight gain, and headache

Back pain, dizziness, and blurry vision

Pain in the left upper quadrant, fever, and sweating

How is liver cirrhosis confirmed?

By blood tests for liver enzymes

Through an MRI of the liver

By performing a liver biopsy (correct)

Through a CT scan of the liver

What is a common complication of advanced liver cirrhosis?

Shortness of breath

Joint pain

Muscle weakness

Jaundice (correct)

What causes ascites in individuals with liver cirrhosis?

Decreased albumin production Signup and view all the answers

Why does intense itching occur in individuals with liver cirrhosis?

When bile products are deposited in the skin Signup and view all the answers

How is end-stage liver cirrhosis typically treated?

Through a liver transplant Signup and view all the answers

What is the function of segmentation in the small intestine?

To mix chyme, accessory digestive organ secretions, and intestinal juice Signup and view all the answers

What initiates the muscular contractions responsible for segmentation in the small intestine?

Pacemaker cells (interstitial cells of Cajal) Signup and view all the answers

How does segmentation differ from peristalsis in terms of movement?

Segmentation involves back-and-forth mixing, peristalsis involves forward movement Signup and view all the answers

Where are the pacemaker cells responsible for initiating segmentation located?

Between the smooth muscle layers of the muscularis in the small intestine wall Signup and view all the answers

At what rate do pacemaker cells depolarize in the duodenum compared to the ileum?

The rate is higher in the duodenum (about 12–14 times per minute) compared to the ileum (about 8–9 times per minute) Signup and view all the answers

How do electrical signals spread through smooth muscle cells during segmentation?

Via gap junctions to allow single-unit smooth muscle to contract Signup and view all the answers

What does a hepatic lobule in the liver look like in cross-section?

A side view of a bicycle wheel Signup and view all the answers

Which blood vessel delivers oxygenated blood to the liver?

Hepatic artery Signup and view all the answers

What is the main function of hepatic sinusoids in the liver lobules?

Transport blood Signup and view all the answers

Which source provides deoxygenated and nutrient-rich blood to the liver?

Hepatic portal vein Signup and view all the answers

What is the approximate percentage of blood volume delivered to the liver by the hepatic portal vein?

75% Signup and view all the answers

How do the hepatic artery and hepatic portal vein branch into smaller vessels?

Form components of portal triads Signup and view all the answers

What is the surgical procedure for the removal of the gallbladder called?

Cholecystectomy Signup and view all the answers

What function of bile is lost after the gallbladder is removed?

Storage of bile Signup and view all the answers

What organ continues to produce bile even after the removal of the gallbladder?

Liver Signup and view all the answers

Which cells in the pancreas produce and secrete hormones like insulin and glucagon?

Endocrine cells Signup and view all the answers

What is the approximate length of the pancreas?

6 to 7 inches Signup and view all the answers

Which type of disorders can have serious effects on the ability to digest and absorb nutrients?

Pancreatic disorders Signup and view all the answers

What type of gland is the pancreas?

Endocrine gland Signup and view all the answers

Which cells does pancreatic cancer most commonly originate from?

Exocrine cells Signup and view all the answers

What is a major risk factor for pancreatic cancer that can double the risk?

Smoking Signup and view all the answers

Why is early detection important for the prognosis of pancreatic cancer?

It allows for more favorable outcomes Signup and view all the answers

Why is early detection of pancreatic cancer difficult?

Lack of a screening test and nonspecific symptoms Signup and view all the answers

What is the approximate length of the large intestine from its origin to its termination?

~1.5 meters (~5 feet) Signup and view all the answers

What is the primary region within the small intestine for nutrient absorption?

Jejunum Signup and view all the answers

Which region of the small intestine forms approximately three-fifths of its length?

Ileum Signup and view all the answers

Which sphincter controls the entry of materials from the small intestine into the large intestine?

Ileocecal valve Signup and view all the answers

What structures in the small intestine increase surface area for absorption?

Circular folds Signup and view all the answers

What are macroscopic structures formed by both the mucosal and submucosal tunics of the small intestine?

Circular folds Signup and view all the answers

Which term refers to the last region of the small intestine?

Ileum Signup and view all the answers

Which type of cells contribute to the process of digestion by producing intestinal juice in the small intestine?

Secretory cells Signup and view all the answers

What is the function of mucin produced by goblet cells in the small intestine?

Lubricating and protecting the intestinal lining Signup and view all the answers

Where are the invaginations of the mucosa that secrete intestinal juice located?

Intestinal glands Signup and view all the answers

Which type of cells secrete hormones into the blood in the small intestine?

Hepatic cells Signup and view all the answers

What is the function of intestinal glands (crypts of Lieberkühn) in the small intestine?

Secreting intestinal juice Signup and view all the answers

What is the role of microvilli in the small intestine?

Projecting into the intestinal lumen Signup and view all the answers

What is the primary function of bile in relation to lipid digestion?

Emulsifying lipids Signup and view all the answers

Where is bile stored, concentrated, and released from?

Gallbladder Signup and view all the answers

Which organ has three tunics - inner mucosa, middle muscularis, and external serosa?

Gallbladder Signup and view all the answers

What is the purpose of the cystic duct connected to the gallbladder?

Connecting to the common bile duct Signup and view all the answers

How does bile contribute to lipid digestion in the gastrointestinal tract?

By mechanically breaking down lipids into smaller aggregates Signup and view all the answers

Which structure controls the flow of bile into and out of the gallbladder?

Sphincter valve Signup and view all the answers

What type of reflex is the defecation reflex?

Monosynaptic reflex Signup and view all the answers

Which action is required for conscious regulation of defecation?

Relaxation of the external anal sphincter Signup and view all the answers

What initiates the defecation reflex?

Sensory perception of stretch in the rectum Signup and view all the answers

What is a common cause of constipation according to the text?

Low fiber diet Signup and view all the answers

Which maneuver is associated with conscious regulation of defecation?

Valsalva maneuver Signup and view all the answers

What is a common side effect of general anesthesia related to bowel function?

Constipation Signup and view all the answers

What term is used to describe the presence of gallstones in the gallbladder?

Cholelithiasis Signup and view all the answers

Which risk factor is NOT associated with the development of gallstones?

Young age Signup and view all the answers

What symptom is typically experienced when a gallstone becomes lodged in the neck of the cystic duct?

Severe pain (biliary colic) Signup and view all the answers

Which region of the body may an individual perceive pain if a gallstone lodges in the neck of the cystic duct?

Right hypochondriac region Signup and view all the answers

If a gallstone leaves the gallbladder and enters the biliary apparatus, what term is used to describe this condition?

Choledocholethiasis Signup and view all the answers

Apart from women, what other demographic group has a higher prevalence of gallstones?

Caucasians Signup and view all the answers

What is the hallmark symptom of Crohn disease?

Severe diarrhea Signup and view all the answers

In ulcerative colitis, which part of the intestine is primarily affected?

Rectum and descending colon Signup and view all the answers

Which layer of the intestinal wall is primarily affected by inflammation in Crohn disease?

Mucosa Signup and view all the answers

What distinguishes Crohn disease from ulcerative colitis in terms of affected regions?

Crohn disease involves areas of healthy intestine between diseased sections. Signup and view all the answers

Which of the following is NOT a symptom commonly associated with inflammatory bowel disease (IBD)?

Jaundice Signup and view all the answers

What distinguishes ulcerative colitis from Crohn disease in terms of affected regions?

Ulcerative colitis causes inflammation in specific areas of the intestines. Signup and view all the answers

Which gastrointestinal disorder is associated with a higher risk of colon cancer?

Ulcerative colitis Signup and view all the answers

What are the symptoms of irritable bowel syndrome (IBS)?

Crampy abdominal pain, bloating, constipation, and diarrhea Signup and view all the answers

What is the approximate prevalence of irritable bowel syndrome (IBS) in the United States?

1 in every five people Signup and view all the answers

How can most people control the symptoms of irritable bowel syndrome (IBS)?

Reducing stress, changing diet, and using certain medications Signup and view all the answers

Which digestive disorder is being studied for treatment using fecal transplants?

Irritable bowel syndrome (IBS) Signup and view all the answers

What distinguishes ulcerative colitis from Crohn disease in terms of inflammation location?

In ulcerative colitis, inflammation is confined to the mucosa. Signup and view all the answers

What is the primary role of microvilli in the small intestine?

Digestion of nutrients immediately before absorption Signup and view all the answers

Where are brush border enzymes located in the small intestine?

Embedded in the microvilli Signup and view all the answers

How do villi in the small intestine contribute to absorption?

By increasing the surface area for absorption Signup and view all the answers

What is the function of a lacteal within a villus?

Absorption of lipids and lipid-soluble vitamins Signup and view all the answers

Which structure in the small intestine contains an arteriole, capillaries, and a venule?

Villi Signup and view all the answers

In which part of the small intestine are villi most numerous and larger?

Jejunum Signup and view all the answers

What is the main function of the hepatopancreatic sphincter located within the ampulla of Vater?

To regulate the flow of bile and pancreatic juice into the duodenum Signup and view all the answers

Which hormone stimulates the relaxation and opening of the hepatopancreatic sphincter to allow the flow of bile and pancreatic juice into the duodenum?

Cholecystokinin (CCK) Signup and view all the answers

What percentage of an adult's body weight does the liver typically constitute?

Exactly 2% Signup and view all the answers

What is located at the porta hepatis of the liver?

An opening where blood vessels, lymphatics, and nerves enter and exit the liver Signup and view all the answers

Which statement accurately describes the liver's role in digestion?

The liver secretes bile that aids in lipid digestion Signup and view all the answers

What is regulated by the hepatopancreatic sphincter located within the ampulla of Vater?

Release of accessory gland secretions like bile and pancreatic juice Signup and view all the answers

What is the role of pacemaker cells in the small intestine?

Spread electrical signals via gap junctions for segmentation Signup and view all the answers

How does the depolarization rate of pacemaker cells differ between the duodenum and ileum?

Depolarization rate varies depending on the segment of the small intestine Signup and view all the answers

Which region of the small intestine has the most frequent rhythm of muscular contraction for segmentation?

Duodenum Signup and view all the answers

What is the primary function of segmentation in the small intestine?

Thoroughly mix chyme and digestive secretions Signup and view all the answers

How do pacemaker cells contribute to the back-and-forth motion of segmentation?

Generate electrical signals for muscular contractions Signup and view all the answers

In what way does segmentation differ from peristalsis in terms of intestinal movement?

Segmentation pushes content forward, while peristalsis mixes chyme Signup and view all the answers

26.3 Lower Gastrointestinal Tract and Associated Accessory Digestive Organs

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Questions and Answers

What symptoms may an individual with faltering liver function experience?

How is liver cirrhosis confirmed?

What is a common complication of advanced liver cirrhosis?

What causes ascites in individuals with liver cirrhosis?

Why does intense itching occur in individuals with liver cirrhosis?

How is end-stage liver cirrhosis typically treated?

What is the function of segmentation in the small intestine?

What initiates the muscular contractions responsible for segmentation in the small intestine?

How does segmentation differ from peristalsis in terms of movement?

Where are the pacemaker cells responsible for initiating segmentation located?

At what rate do pacemaker cells depolarize in the duodenum compared to the ileum?

How do electrical signals spread through smooth muscle cells during segmentation?

What does a hepatic lobule in the liver look like in cross-section?

Which blood vessel delivers oxygenated blood to the liver?

What is the main function of hepatic sinusoids in the liver lobules?

Which source provides deoxygenated and nutrient-rich blood to the liver?

What is the approximate percentage of blood volume delivered to the liver by the hepatic portal vein?

How do the hepatic artery and hepatic portal vein branch into smaller vessels?

What is the surgical procedure for the removal of the gallbladder called?

What function of bile is lost after the gallbladder is removed?

What organ continues to produce bile even after the removal of the gallbladder?

Which cells in the pancreas produce and secrete hormones like insulin and glucagon?

What is the approximate length of the pancreas?

Which type of disorders can have serious effects on the ability to digest and absorb nutrients?

What type of gland is the pancreas?

Which cells does pancreatic cancer most commonly originate from?

What is a major risk factor for pancreatic cancer that can double the risk?

Why is early detection important for the prognosis of pancreatic cancer?

Why is early detection of pancreatic cancer difficult?

What is the approximate length of the large intestine from its origin to its termination?

What is the primary region within the small intestine for nutrient absorption?

Which region of the small intestine forms approximately three-fifths of its length?

Which sphincter controls the entry of materials from the small intestine into the large intestine?

What structures in the small intestine increase surface area for absorption?

What are macroscopic structures formed by both the mucosal and submucosal tunics of the small intestine?

Which term refers to the last region of the small intestine?

Which type of cells contribute to the process of digestion by producing intestinal juice in the small intestine?

What is the function of mucin produced by goblet cells in the small intestine?

Where are the invaginations of the mucosa that secrete intestinal juice located?

Which type of cells secrete hormones into the blood in the small intestine?

What is the function of intestinal glands (crypts of Lieberkühn) in the small intestine?

What is the role of microvilli in the small intestine?

What is the primary function of bile in relation to lipid digestion?

Where is bile stored, concentrated, and released from?

Which organ has three tunics - inner mucosa, middle muscularis, and external serosa?

What is the purpose of the cystic duct connected to the gallbladder?

How does bile contribute to lipid digestion in the gastrointestinal tract?

Which structure controls the flow of bile into and out of the gallbladder?

What type of reflex is the defecation reflex?

Which action is required for conscious regulation of defecation?

What initiates the defecation reflex?

What is a common cause of constipation according to the text?

Which maneuver is associated with conscious regulation of defecation?

What is a common side effect of general anesthesia related to bowel function?

What term is used to describe the presence of gallstones in the gallbladder?

Which risk factor is NOT associated with the development of gallstones?

What symptom is typically experienced when a gallstone becomes lodged in the neck of the cystic duct?

Which region of the body may an individual perceive pain if a gallstone lodges in the neck of the cystic duct?

If a gallstone leaves the gallbladder and enters the biliary apparatus, what term is used to describe this condition?

Apart from women, what other demographic group has a higher prevalence of gallstones?

What is the hallmark symptom of Crohn disease?

In ulcerative colitis, which part of the intestine is primarily affected?

Which layer of the intestinal wall is primarily affected by inflammation in Crohn disease?

What distinguishes Crohn disease from ulcerative colitis in terms of affected regions?

Which of the following is NOT a symptom commonly associated with inflammatory bowel disease (IBD)?

What distinguishes ulcerative colitis from Crohn disease in terms of affected regions?

Which gastrointestinal disorder is associated with a higher risk of colon cancer?

What are the symptoms of irritable bowel syndrome (IBS)?

What is the approximate prevalence of irritable bowel syndrome (IBS) in the United States?

How can most people control the symptoms of irritable bowel syndrome (IBS)?

Which digestive disorder is being studied for treatment using fecal transplants?

What distinguishes ulcerative colitis from Crohn disease in terms of inflammation location?

What is the primary role of microvilli in the small intestine?

Where are brush border enzymes located in the small intestine?

How do villi in the small intestine contribute to absorption?

What is the function of a lacteal within a villus?