Digestion Set 4 MCQs

Q1 | Which of the following statements is correct?:

The gastric juice contains pepsins,gelatinase,lipase and α-amylase enzymes.

The only essential constituent of the gastric juice is the intrinsic factor.

The hunger contractions disappear after bilateral vagotomy or damage of the feeding center in the hypothalamus.

HCL is essential for both carbohydrate and fat digestion.

Q2 | Which of the following is the major factor that protects the duodenal mucosa from the damage by gastric acid?:

Pancreatic bicarbonate secretions.

The endogenous mucosal barrier of the duodenum.

Duodenal bicarbonate secretion,

Hepatic bicarbonate secretion.

Q3 | Which of the following substances is released from the duodenal mucosa in response to acidic gastric juice?:

CCK

Substance P

Secretin

GIP

Q4 | A 42years old salesman presents with the chief complaint of intermittent midepigastric pain that is relieved by antacids or eating. Gatric analysis reveals that basal and maximal acid output exceed normal values. The gastric hypersecretion can be explained by an increase in the plasma concentration of which of the following?:

Somatostatin

Histamine

Gastrin

Secretin

Q5 | Removal of the stomach can lead to all of the following except:

Marked digestive disturbances

Megaloblastic anaemia (pernicious anaemia)

A fall in the plasma volume after a heavy meal (due to the dumping syndrome)

Diminished Ca⁺⁺ absorption and weak development of bones

Q6 | HCl secretion includes all the following processes except:

Active transport of H⁺ into gastric lumen

H⁺ is exchanged for K⁺ from the extracellular fluid

HCO₃⁻ diffuse into the extracellular fluid in exchange for Cl⁻

It’s associated with production of a postprandial alkaline tide

Q7 | The gastric juice has all the following characteristics except:

It contains an alkaline secretion from the surface epithelium

It’s PH is always less than 3

It contains the intrinsic factor which is essential for vit.B₁₂ absorption

It’s antibacterial action is produced by its mucous content

Q8 | Gastric secretion is inhibited by all the following except:

Presence of excess H⁺ in the pyloric antrum

Presence of excess protein digestive products in the stomach

Certain emotions e.g. fear and depression

Certain GIT hormones e.g. secretin,CCK and VIP

Q9 | Concerning HCl secretion, all the following is true except:

It’s associated with increased PH of the gastric venous blood

It’s stimulated by gastrin, acetylcholine,histamine and norepinephiren

The energy required is derived from ATP breakdown

It involves formation of carbonic acid

Q10 | All the following statements are true except:

VIP stimulates intestinal secretion and inhibits gastric acid secretions

Diamox (a carbonic anhydrase inhibitor) increases both gastric HCL formation and the HCO₃⁻ content in the pancreatic juice

Both gastrin and glucagons are secreted from the pyloric antrum and duodenum

Gastrin is secreted from almost the whole GIT mucosa

Q11 | Which of the following statement is wrong?:

The gastric peristalsis includes propulsive,mixing and grinding movements

The cephalic phase of gastric secretion involves no release of gastrin.

Deficiency of the intrinsic factor causes pernicious anaemia.

Large doses of gastrin cause contraction of the pyloric sphincter.

Q12 | The following statements about gastric secretion are correct except:

Gastric secretion increases when a hungry person thinks about food

Gastric secretion helps vit.B₁₂ absorption

Production of HCl depends on activity of carbonic anhydrase

Gastric secretion is associated with increased H⁺ concentrarion in venous blood coming from stomach

Q13 | hich of the following statements about gastric secretion is incorrect:

Gastric acid secretion can be inhibited by somatostatin

The main phase of gastric secretion is the gastric phase

Gastric secretion increases in response to the presence of food in mouth after the vagi to stomach have been cut

none

Q14 | A 55 years old man with a history of chronic alcohol consumption presents to his local physician with non specific complaints of dyspepsia. Examination and diagnostic testing reveal that he has destruction of the gastric glands. The condition would predispose the patient to which of the following?:

Steatorrhea

Gastric hypomotility

Gastric ulcer

Anaemia

Q15 | Which of the following statement about motor function of stomachis untrue?:

The frequency of gastric peristaltic contraction is about 3/min

Fasting hypoglycemia produces hunger contractions

The enterogastric reflex stimulates gastric emptying

none

Q16 | Which of the following statement about motor function of stomach is untrue?:

Motility of stomach increases when fat enters duodenum

MMC prevents duodenogastric reflex

Receptive relaxation of stomach is mediated by purinergic vagal fibers

non

Q17 | Vomiting:

occur only in a denervated stomach

Occurs by strong contraction of the stomach wall

May be produced by conditioned reflex

occur only in an empty stomach

Q18 | Vomiting:

Leads to expulsion of gastric contetnts by violent rhythmic contractions of gut smooth ms.

Is coordinated by a mid-brain vomiting center

Of green fluid suggests that duodenal contents have regurgitated into the stomach

May be accompanied by a fall in arterial blood pressure

Q19 | The so-called chemoreceptor trigger zone:

Is synonymous with the vomiting center

Is located in the cerebral peduncles, ventral to the Aqueduct of Sylvius

Is sensitive to the action of morphine

May be destroyed experimentally ; the ablation of both chemoreceptor trigger zones abolishes all forms of vomiting

Q20 | As regards the process of vomiting:

Its is controlled by a center in the cerebral cortex

It always begins with nausea

Prolonged vomiting usually produces dehydration associated with acidosis

It’s associated with relaxation of the body and fundus of the stomach

Q21 | A pyloric obstruction in an infant which results in a prolonged bout of sever vomiting is likely to cause a primary:

Metabolic acidosis

Metabolic alkalosis

Respiratory acidosis

Respiratory alkalosis

Q22 | An obstruction of the small bowel leading to sever vomiting with a preponderant loss of duodenal contents is likely to cause a primary:

Metabolic acidosis

Metabolis alkalosis

Respiratory acidosis

Respiratory alkalosis

Q23 | A likely reason why a to and fro motion, such as that encountered during airplane flights or in an automobile ride over a bumpy road, tends to cause nausea and vomiting, is because during such motions:

Much air is swallowed and the stomach becomes distended

The stomach is more likely to develop reverse peristalsis

The cerebral cortex can no longer inhibit an intrinsic tendency of the brainstem to cause vomiting

Vestibular reflex eventually excite a chemoreceptor trigger zone in the medulla

Q24 | Select a single incorrect answer about vomiting:

Vomiting center is in hypothalamus

The role of stomach is passive in the process of vomiting

Vomiting may occur as a conditioned reflex

none

Q25 | Trypsinogen in pancreatic juice is activated by:

Alkaline PH

Enterokinase

Bile salts

none