Question 1

Which of the following best describes the difference between mechanical and chemical digestion in the human digestive system?

Accepted Answer

Mechanical digestion refers to the physical breakdown of food into smaller pieces, while chemical digestion involves enzymatic hydrolysis of macromolecules into absorbable units.

Question 2

During the digestion of complex carbohydrates, which enzyme initiates the breakdown in the mouth, and what is the primary end product absorbed in the small intestine?

Accepted Answer

Salivary amylase; glucose

Question 3

A patient has a deficiency in bile production. Which step in triglyceride digestion and absorption would be most directly affected?

Accepted Answer

Emulsification of fats in the small intestine

Question 4

Which of the following correctly traces the breakdown and absorption pathway of dietary proteins?

Accepted Answer

Proteins → peptides (by pepsin in stomach) → amino acids (by pancreatic and brush border enzymes) → absorbed into blood capillaries

Question 5

Which hormone is primarily elevated during the absorptive state and promotes the uptake and storage of glucose, fatty acids, and amino acids?

Accepted Answer

Insulin

Question 6

During the postabsorptive state, which process is most responsible for maintaining blood glucose levels?

Accepted Answer

Glycogenolysis

Question 7

Which of the following best explains how glucose can be converted to fat in the body?

Accepted Answer

Excess glucose is converted to glycogen, and when glycogen stores are full, glucose is converted to fatty acids via lipogenesis.

Question 8

A patient is fasting for 24 hours. Which hormone is likely to be elevated, and what is its primary effect on nutrient metabolism?

Accepted Answer

Glucagon; stimulates glycogenolysis and gluconeogenesis

Question 9

Which process describes the formation of glucose from non-carbohydrate sources, and which macronutrient can be used in this process?

Accepted Answer

Gluconeogenesis; proteins

Question 10

Which of the following hormones promotes catabolism and is elevated during the postabsorptive state?

Accepted Answer

Glucagon

Question 11

A person with type 1 diabetes mellitus forgets to take their insulin. Which metabolic changes are most likely to occur?

Accepted Answer

Decreased glucose uptake by cells and increased gluconeogenesis

Question 12

Which of the following best describes the effect of epinephrine on nutrient metabolism during a 'fight or flight' response?

Accepted Answer

Stimulates glycogenolysis and lipolysis to increase blood glucose and fatty acids

Question 13

Which of the following is a key difference between diabetes mellitus and hypoglycemia?

Accepted Answer

Diabetes mellitus is characterized by chronic high blood glucose, while hypoglycemia is characterized by abnormally low blood glucose.

Question 14

Which of the following best describes the role of glucocorticoids (such as cortisol) in nutrient metabolism during prolonged stress?

Accepted Answer

They promote gluconeogenesis and protein breakdown to increase blood glucose.

Question 15

Which equation correctly represents the hydrolysis of a triglyceride during digestion?

Accepted Answer

$$\mathrm{Triglyceride} + 3\ H_2O \rightarrow \mathrm{Glycerol} + 3\ \mathrm{Fatty\ acids}$$

Question 16

Which of the following scenarios best illustrates the process of nutrient absorption in the small intestine?

Accepted Answer

Amino acids are absorbed into blood capillaries via active transport, while fatty acids are packaged into chylomicrons and absorbed into lacteals.

Question 17

Which of the following best describes the relationship between glycogen and glucose in the human body?

Accepted Answer

Glucose is stored as glycogen in the liver and muscles during the absorptive state.

Question 18

Which of the following is a correct sequence of events during the chemical digestion of starch?

Accepted Answer

Salivary amylase breaks down starch to maltose in the mouth; pancreatic amylase continues digestion in the small intestine; brush border enzymes convert maltose to glucose.

Question 19

Which of the following best explains why protein is not the body's preferred energy source during the postabsorptive state?

Accepted Answer

Proteins are primarily used for structural and functional roles, and excessive breakdown can impair body function.

Digestive Physiology & Nutrient Regulation: Digestion, Absorption, and Metabolic Regulation

Study Guide - Practice Questions

Study Guide - Flashcards