Deck 64: Propulsion and Mixing of Food in the Alimentary Tract

Question 1

A 20-year-old man has his spinal cord severed at T6 in an automobile accident. He devises a method to distend the rectum to initiate the rectosphincteric reflex. Rectal distention causes which of the following?

Answer 1

C

Question 2

Which of the following structures is critical for determining whether a bolus of food is small enough to be swallowed?

A)Epiglottis
B)Larynx
C)Palatopharyngeal folds
D)Soft palate
E)Upper esophageal sphincter

Answer 2

C

Question 3

Migrating motility complexes are thought to be stimulated by which of the following?

A)Cholecystokinin
B)Gastrin
C)Mass movements
D)Motilin
E)Vasoactive intestinal peptide

Answer 3

D

Question 4

A newborn boy does not pass meconium in the first 24 hours. His abdomen is distended, and he begins vomiting. Various other tests lead to a diagnosis of Hirschsprung's disease. An obstruction is most likely to be found in which portion of the gut?

A)Ascending colon
B)Ileocecal sphincter
C)Lower esophageal sphincter
D)Pylorus
E)Sigmoid colon

Question 5

Which of the following best describes the direct physiological effect of the various hormones on gastric emptying?

Question 6

Mass movements are often stimulated after a meal by distention of the stomach and distention of the duodenum. Mass movements often lead to which of the following?

A)Bowel movements
B)Gastric movements
C)Haustrations
D)Esophageal contractions
E)Pharyngeal peristalsis

Question 7

Mass movements in the large intestine cause which of the following?

A)Contraction of internal anal sphincter
B)Duodenal peristalsis
C)Gastric retropulsion
D)Hunger sensations
E)Rectal distention

Question 8

Which one of the following manometric recordings illustrates normal function of the esophagus at mid-thoracic level before and after swallowing (arrow)? The dashed lines represent a pressure of 0 mm Hg.

Question 9

Ileocecal sphincter tone decreases (relaxes) after distention of which structure?

A)Colon
B)Esophagus
C)Ileum
D)Pharynx
E)Rectum

Question 10

Which of the following elements of the defecation apparatus requires input from higher centers of the brain in a healthy person under normal conditions?

A)Peristaltic contractions of the sigmoid colon
B)Rectal distention
C)Rectal peristalsis
D)Constriction of external anal sphincter
E)Constriction of internal anal sphincter

Question 11

Distention of the rectum causes a reflex relaxation of which structure?

A)Abdominal muscle
B)Diaphragm
C)External anal sphincter
D)Internal anal sphincter
E)Sigmoid colon

Question 12

Mass movements are often stimulated after a meal by which reflex?

A)Coloileal reflex
B)Enterogastric reflex
C)Gastrocolic reflex
D)Intestino-intestinal reflex
E)Rectosphincteric reflex

Question 13

A healthy 29-year-old man eats a breakfast of eggs, bacon, and toast. A decrease in which of the following delays gastric emptying?

A)Intestinal peristalsis
B)Pyloric tone
C)Segmentation contractions in small intestine
D)Tone of orad stomach

Question 14

A 39-year-old man has from chest pain when he eats, especially meat. He also belches excessively and has heartburn. His wife complains about his bad breath. The radiograph shows a dilated esophagus, and achalasia is suspected. Esophageal manometry confirms the diagnosis. Which one of the pressure tracings given below was taken at the lower esophageal sphincter of this patient before and after swallowing (arrow)? The dashed line represents a pressure of 0 mm Hg.

Question 15

The primary purpose of migrating motility complexes is which of the following?

A)Move chyme through the small intestine during a meal
B)Promote gastric emptying as a meal is digested
C)Stimulation of mass movements
D)Sweep undigested residue toward the colon

Question 16

Which of the following occur during the act of vomiting?

Question 17

Which one of the following manometric recordings illustrates normal function of the esophagus at a point below the diaphragm before and after swallowing (arrow)? The dashed lines represent a pressure of 0 mm Hg.

Question 18

The main mixing movement of the stomach is which of the following?

A)Primary peristalsis
B)Receptive relaxation
C)Retropulsion
D)Segmentation contractions

Question 19

The ileocecal junction functions as a valve and a sphincter. Ileocecal sphincter tone increases after distention of which of the following?

A)Colon
B)Esophagus
C)Ileum
D)Rectum
E)Stomach

Question 20

Achalasia is associated with which of the following at rest and during swallowing?

A)Higher than normal pressure at lower esophageal sphincter
B)Lower than normal pressure at lower esophageal sphincter
C)Higher than normal pressure at upper esophageal sphincter
D)Lower than normal pressure at upper esophageal sphincter

Question 21

A newborn boy does not pass meconium in the first 24 hours. His abdomen is distended, and he begins vomiting. Hirschsprung's disease is suspected. Which of the following is virtually absent from the constricted segment of the colon in this patient?

A)Blood flow
B)Circular smooth muscle
C)Ganglion cells
D)Mucosa
E)Serosa

Question 22

Receptive relaxation of the fundus is mediated by which substance?

A)Amino acids
B)Gastrin
C)Glucose-dependent insulinotropic peptide
D)Secretin
E)Vasoactive intestinal peptide

Question 23

An 87-year-old man has a stroke that eliminates vagal nerve input to the gastrointestinal tract and severely curtails function of the glossopharyngeal nerve. Which of the following is operational in this man?

A)Pharyngeal phase of swallowing
B)Primary peristalsis of the esophagus
C)Receptive relaxation of the fundus
D)Receptive relaxation of the lower esophageal sphincter
E)Secondary peristalsis of the esophagus

Question 24

Which of the following reflexes results in the urge to defecate when the duodenum is distended?

A)Duodenocolic reflex
B)Enterogastric reflex
C)Gastrocolic reflex
D)Ileocecal reflex
E)Intestino-intestinal reflex

Question 25

Which one of the pressure tracings given below illustrates normal function of the lower esophageal sphincter before and after swallowing (arrow)? The dashed line represents a pressure of 0 mm Hg.

Question 26

A person sustaining a stroke can have trouble swallowing because a stroke can cause damage to the swallowing center.

A)Both the statement and the reason are correct and related.
B)Both the statement and the reason are correct but not related.
C)The statement is correct, but the reason is not.
D)The statement is not correct, but the reason is correct.
E)Neither the statement nor the reason is correct.

Question 27

Conditions that tend to increase gastric emptying include which of the following?

A)Decreased peristalsis in stomach
B)Increased tone of orad stomach
C)Increased tone of pylorus
D)Segmentation contractions in intestine

Question 28

A 52-year-old man eats a healthy meal. Approximately 20 minutes later, the man has the urge to defecate. Which of the following reflexes results in the urge to defecate when the stomach is stretched?

A)Duodenocolic reflex
B)Enterogastric reflex
C)Gastrocolic reflex
D)Ileocecal reflex
E)Intestine-intestinal reflex

Question 29

Ileocecal sphincter tone decreases after distention of which of the following?

A)Colon
B)Esophagus
C)Ileum
D)Rectum
E)Stomach

Question 30

A 43-year-old medical student suffers severe damage to the conus medullaris in an accident. He initiates defecation by inserting a balloon-tipped Foley catheter into his rectum and inflating the balloon with a 50 mL syringe. Which reflex is stimulated by the balloon in this patient?

A)Duodenocolic reflex
B)Enterogastric reflex
C)Ileocecal reflex
D)Intrinsic defecation reflex
E)Spinal cord reflex

Question 31

A 19-year-old man is admitted to the emergency department after an automobile accident. A CT scan shows that the spinal cord is severed at T5. Balloon distension of the rectum is most likely to cause which of the following in this patient?

Question 32

The diagram shows manometric recordings from a patient before and after pelvic floor training. A balloon placed in the rectum was inflated (arrows) and deflated repeatedly. Tracing Z is a manometric recording obtained from the external anal sphincter before and after pelvic floor training. Which of the following best describe the origin of tracing X?

A)Distal rectum
B)Ileocecal valve
C)Internal anal sphincter
D)Lower esophageal sphincter
E)Proximal rectum

Question 33

Parasympathetic stimulation can increase intestinal motility because parasympathetic stimulation increases slow wave frequency.

A)Both the statement and the reason are correct and related.
B)Both the statement and the reason are correct but not related.
C)The statement is correct, but the reason is not.
D)The statement is not correct, but the reason is correct.
E)Neither the statement nor the reason is correct.