Question 1

Which of the following best describes the main function of the hepatic portal system as shown in the fourth image?

Accepted Answer

It carries nutrient-rich blood from the digestive organs to the liver for processing.

Question 2

Which layer of the gastrointestinal tract wall is primarily responsible for peristalsis and segmentation, as illustrated in the third image?

Accepted Answer

Muscularis

Question 3

A patient has difficulty absorbing fat-soluble vitamins (A, D, E, K). Which organ is most likely malfunctioning?

Accepted Answer

Liver

Question 4

Which process is responsible for moving food through the esophagus to the stomach, as shown in the third image?

Accepted Answer

Peristalsis

Question 5

Which of the following is NOT a function of the large intestine, as depicted in the fifth image?

Accepted Answer

Digestion of proteins

Question 6

Which enzyme is responsible for the initial breakdown of starch in the mouth?

Accepted Answer

Salivary amylase

Question 7

A person with a damaged lower esophageal sphincter is most likely to experience which condition?

Accepted Answer

Acid reflux (heartburn)

Question 8

Which of the following best explains why peptic ulcers can develop in the stomach?

Accepted Answer

Damage to the protective mucus barrier, often due to Helicobacter pylori infection

Question 9

Which of the following nutrients is absorbed primarily by active transport into intestinal epithelial cells?

Accepted Answer

Amino acids

Question 10

If the pancreas fails to secrete sodium bicarbonate, what is the most likely consequence in the small intestine?

Accepted Answer

The pH will remain too acidic for optimal enzyme activity.

Question 11

Which of the following best describes the role of bile in digestion?

Accepted Answer

It emulsifies lipids, increasing their surface area for enzyme action.

Question 12

Which of the following is a correct statement about energy balance and body weight?

Accepted Answer

A caloric deficit of 3,500 calories results in the loss of approximately one pound of fat.

Question 13

Which of the following is a function of the intestinal microbiota in the large intestine?

Accepted Answer

Synthesis of vitamin K

Question 14

A patient is unable to digest lactose and experiences gas and bloating after consuming dairy. What is the most likely explanation?

Accepted Answer

They lack the enzyme lactase.

Question 15

Which of the following statements about vitamins is correct?

Accepted Answer

Fat-soluble vitamins are stored in adipose tissue and do not need to be consumed daily.

Question 16

Which of the following best describes the absorption of water in the digestive tract?

Accepted Answer

Water is absorbed by osmosis in both the small and large intestines.

Question 17

Which of the following is a complete protein source?

Accepted Answer

Soy protein

Question 18

Which of the following dietary fats is most likely to raise LDL ('bad') cholesterol levels?

Accepted Answer

Saturated fats

Question 19

Which of the following is a trace mineral required in the human diet?

Accepted Answer

Iron

Question 20

Which of the following best explains why vegetarians must combine different plant sources of protein?

Accepted Answer

Most plant proteins are incomplete and lack one or more essential amino acids.

Digestive System: Structure, Function, and Nutrition

Study Guide - Practice Questions