Question 1

Which physical mechanism of digestion is responsible for mixing food with gastric juices in the stomach, and what is its primary function?

Accepted Answer

Gastric churning; its primary function is to mix and digest food in the stomach.

Question 2

A patient has a deficiency in bile production. Which digestive process will be most affected and why?

Accepted Answer

Lipid digestion, because bile emulsifies fats and increases surface area for lipase action.

Question 3

Which hormone is released in response to stomach distension and stimulates the secretion of gastric juice?

Accepted Answer

Gastrin

Question 4

During carbohydrate digestion, which enzyme is responsible for breaking down starch into maltose in the mouth?

Accepted Answer

Salivary amylase

Question 5

If the pH in the stomach is 2, what will happen to the activity of salivary amylase?

Accepted Answer

It will be denatured, resulting in decreased starch digestion.

Question 6

Which of the following best describes the effect of boiling on digestive enzymes?

Accepted Answer

Boiling denatures enzymes, preventing them from digesting substrates.

Question 7

A patient with diabetes mellitus is unable to produce sufficient insulin. Which metabolic pathway will be most affected?

Accepted Answer

Glycogenolysis will be stimulated, leading to increased blood glucose.

Question 8

Which digestive enzyme is produced by the pancreas and acts in the duodenum to break down proteins into dipeptides?

Accepted Answer

Trypsin

Question 9

What is the primary function of bicarbonate ion ($$\mathrm{$$HCO_3$$^-}) $$secreted by the pancreatic duct?

Accepted Answer

To neutralize acidic chyme entering the duodenum.

Question 10

Which of the following correctly matches the enzyme with its substrate and end product in carbohydrate digestion?

Accepted Answer

Maltase; substrate: maltose; end product: glucose + glucose

Question 11

A patient’s assay results show both positive starch and positive maltose. What does this indicate about the enzymatic breakdown?

Accepted Answer

Incomplete breakdown; some enzyme was still active but not all starch was digested.

Question 12

Which hormone stimulates the release of bile from the gallbladder and digestive enzymes from the pancreas?

Accepted Answer

Cholecystokinin (CCK)

Question 13

Which physical mechanism is responsible for moving food through the esophagus to the stomach?

Accepted Answer

Peristalsis

Question 14

Which of the following is NOT a function of hydrochloric acid (HCl) in the stomach?

Accepted Answer

Emulsifying fats

Question 15

Which enzyme is responsible for the final step in protein digestion, releasing free amino acids from dipeptides?

Accepted Answer

Carboxypeptidase

Question 16

If a patient’s small intestine is unable to produce lactase, which dietary component will be poorly digested?

Accepted Answer

Lactose

Question 17

Which of the following best describes the pathway for lipid digestion?

Accepted Answer

Triglycerides $$\rightarrow$$ glycerol + 3 fatty acids

Question 18

Which enzyme is responsible for the breakdown of nucleic acids in the duodenum?

Accepted Answer

Deoxyribonuclease (DNAse)

Question 19

Which metabolic process is stimulated by insulin during the absorptive state?

Accepted Answer

Glycogenesis

Question 20

A patient is unable to digest starch in the duodenum due to a lack of pancreatic amylase. Which intermediate product will be absent?

Accepted Answer

Maltose

Digestive System, Part II & Metabolism: Physical and Chemical Mechanisms, Hormonal Regulation, and Enzymatic Pathways

Study Guide - Practice Questions