$$\text{Protein (native)} + \text{HCl} \rightarrow \text{Protein (denatured)}$$

Question 1

Which of the following best describes the primary function of the pharynx and esophagus in the digestive system?

Accepted Answer

Propulsion of food from the mouth to the stomach

Question 2

A patient presents with frequent acid reflux. Which anatomical structure is most likely malfunctioning?

Accepted Answer

Gastroesophageal sphincter

Question 3

During swallowing, which phase is voluntary and involves the contraction of the tongue?

Accepted Answer

Buccal phase

Question 4

The stomach is able to churn and mix food more effectively than the esophagus due to which unique anatomical feature?

Accepted Answer

Oblique (diagonal) muscle layer in the muscularis externa

Question 5

Which cell type in the gastric glands secretes a substance necessary for vitamin B12 absorption?

Accepted Answer

Parietal cells

Question 6

A patient with a deficiency in intrinsic factor is most likely to develop which condition?

Accepted Answer

Pernicious anemia

Question 7

Which of the following best explains why the stomach does not digest itself under normal conditions?

Accepted Answer

All of the above

Question 8

Which hormone is primarily responsible for stimulating HCl secretion in the stomach?

Accepted Answer

Gastrin

Question 9

If the vagus nerve is damaged, which of the following is most likely to occur?

Accepted Answer

Decreased gastric secretion

Question 10

Which of the following best describes the process by which pepsinogen is converted to pepsin in the stomach?

Accepted Answer

Pepsinogen is activated by HCl and pepsin itself (positive feedback)

Question 11

A patient consumes a meal high in fat. How will this affect gastric emptying?

Accepted Answer

Gastric emptying will be slower than normal

Question 12

Which of the following is NOT a function of the stomach?

Accepted Answer

Absorption of most nutrients

Question 13

Which anatomical region of the stomach is directly connected to the esophagus?

Accepted Answer

Cardia

Question 14

Which of the following best describes the role of the muscularis externa in the stomach?

Accepted Answer

Provides three layers of smooth muscle for churning and mixing food

Question 15

Which of the following best explains why the esophagus is normally collapsed when not propelling food?

Accepted Answer

To minimize friction and allow expansion only when needed

Question 16

Which of the following is a direct result of the action of parietal cells in the stomach?

Accepted Answer

Activation of pepsinogen to pepsin

Question 17

Which of the following equations best represents the denaturation of proteins by hydrochloric acid in the stomach?

Accepted Answer

$$	ext{Protein (native)} + 	ext{HCl} ightarrow 	ext{Protein (denatured)}$$

Question 18

Which of the following best describes the role of tight junctions between epithelial cells in the stomach?

Accepted Answer

They prevent gastric juice from seeping into underlying tissue

Question 19

Which phase of gastric secretion is triggered by the sight, smell, taste, or thought of food?

Accepted Answer

Cephalic (reflex) phase

Question 20

A patient has a mutation that prevents the secretion of somatostatin in the stomach. Which of the following is the most likely consequence?

Accepted Answer

Increased gastric acid secretion

Pharynx, Esophagus, and Stomach: Structure and Function in Digestion

Study Guide - Practice Questions