Question 1

Which of the following best describes the difference between amylose and amylopectin, as shown in the provided diagrams?

Accepted Answer

Amylose is a linear chain of glucose molecules, while amylopectin is a branched chain of glucose molecules.

Question 2

Which enzyme initiates the chemical digestion of starch in the mouth, and what is the main product of this reaction?

Accepted Answer

Salivary amylase; dextrins and maltose

Question 3

A patient with lactose intolerance lacks which enzyme, and what are the likely symptoms after consuming dairy?

Accepted Answer

Lactase; bloating, gas, and diarrhea

Question 4

Which of the following statements about the glycemic index (GI) is correct?

Accepted Answer

Foods with a low GI cause a slower, smaller rise in blood glucose compared to high GI foods.

Question 5

Which of the following is a correct chemical formula for glucose, and what does it indicate about its composition?

Accepted Answer

$$\mathrm{C_6H_{12}O_6$}$$; it contains six carbons, twelve hydrogens, and six oxygens in a 1:2:1 ratio.

Question 6

Which of the following best explains why fiber is beneficial for health, based on the study materials?

Accepted Answer

Fiber slows glucose absorption, supports gut health, and reduces the risk of obesity and chronic diseases.

Question 7

Which of the following is a disaccharide composed of glucose and fructose, and is commonly known as table sugar?

Accepted Answer

Sucrose

Question 8

What is the primary function of insulin in carbohydrate metabolism?

Accepted Answer

It promotes the uptake of glucose into cells and storage as glycogen.

Question 9

Which of the following best describes the fate of excess glucose in the body?

Accepted Answer

It is stored as glycogen in the liver and muscles.

Question 10

A food label claims 'high fiber.' According to FDA definitions, what does this mean?

Accepted Answer

The food contains at least 20% of the daily value of fiber per serving.

Question 11

Which of the following statements about fructose is supported by the study materials?

Accepted Answer

Fructose is primarily metabolized in the liver and is not a direct energy source for most body cells.

Question 12

Which of the following best explains the 'protein-sparing' effect of carbohydrates?

Accepted Answer

Adequate carbohydrate intake prevents the breakdown of muscle protein for gluconeogenesis.

Question 13

Which of the following artificial sweeteners must be avoided by individuals with phenylketonuria (PKU), and why?

Accepted Answer

Aspartame; it contains phenylalanine, which cannot be metabolized by people with PKU.

Question 14

Which of the following best describes the effect of a fiber-rich meal on blood glucose levels compared to a low-fiber meal?

Accepted Answer

A fiber-rich meal causes a slower and lower rise in blood glucose after eating.

Question 15

Which of the following is NOT a function of carbohydrates in the human body?

Accepted Answer

Serving as a major component of cell membranes

Question 16

Which of the following best explains why sugar alcohols are used in sugar-free chewing gum?

Accepted Answer

They are not metabolized by oral bacteria, so they do not cause tooth decay.

Question 17

Which of the following is a correct example of a polysaccharide and its primary function?

Accepted Answer

Glycogen; energy storage in animals

Question 18

A person consumes a meal high in carbohydrates. Which hormone is released, and what is its effect on blood glucose?

Accepted Answer

Insulin; it lowers blood glucose by promoting cellular uptake and glycogen synthesis.

Question 19

Which of the following best describes the structure of cellulose and its role in the human diet?

Accepted Answer

Cellulose is a linear polysaccharide of glucose that provides insoluble fiber, supporting digestive health.

Comprehensive Study Notes: Carbohydrates in Human Nutrition

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