BIOL 202L LAB 17 WORKSHEET 2026/2027 | Nutrition
- Macronutrients, Micronutrients & Metabolism |
Complete Answers | Pass Guaranteed - A+ Graded
Section 1: Macronutrients - Carbohydrates, Lipids & Proteins (Q1-18)
Q1. A 24-year-old athlete consumes 2,500 kcal/day. According to USDA Dietary
Guidelines, what is the maximum recommended daily intake of added sugars?
A. 125 kcal (31 g)
B. 250 kcal (62 g)
C. 375 kcal (94 g)
D. 500 kcal (125 g)
Correct Answer: B
Rationale: The USDA Dietary Guidelines recommend limiting added sugars to less
than 10% of total daily calories. For a 2,500 kcal diet, 10% equals 250 kcal. Since
carbohydrates provide 4 kcal/g, this corresponds to approximately 62 g of added
sugars. [CORRECT]
Q2. A patient with lactose intolerance experiences bloating and diarrhea after
consuming dairy products. Which enzyme deficiency is responsible for this
condition?
A. Sucrase
B. Maltase
C. Lactase
D. Amylase
Correct Answer: C
Rationale: Lactase is the brush border disaccharidase that hydrolyzes lactose into
glucose and galactose. A deficiency in lactase prevents lactose digestion, leading to
osmotic diarrhea and bacterial fermentation in the colon, causing bloating and gas.
[CORRECT]
,2
Q3. During digestion, salivary amylase begins carbohydrate breakdown in the mouth.
What is the optimal pH for pancreatic amylase activity in the small intestine?
A. pH 2.0
B. pH 4.0
C. pH 6.7-7.0
D. pH 8.0-9.0
Correct Answer: C
Rationale: Pancreatic amylase functions optimally at a near-neutral pH of 6.7-7.0 in
the small intestine. This differs from salivary amylase (optimal pH ~6.7) and gastric
enzymes that function in acidic environments. The pancreatic bicarbonate secretion
neutralizes gastric acid to create this optimal environment. [CORRECT]
Q4. A nutritionist is counseling a diabetic patient about carbohydrate choices. Which
food would have the LOWEST glycemic index?
A. White bread
B. Baked potato
C. Steel-cut oats
D. Watermelon
Correct Answer: C
Rationale: Steel-cut oats have a low glycemic index (GI ~42-55) due to their high
soluble fiber content and minimal processing, which slows glucose absorption. White
bread (GI ~70-75), baked potatoes (GI ~85), and watermelon (GI ~72) have higher
GIs due to rapid starch digestion or high simple sugar content. [CORRECT]
Q5. Which transport protein is primarily responsible for glucose absorption across
the apical membrane of intestinal enterocytes?
, 3
A. GLUT4
B. SGLT1
C. GLUT2
D. GLUT5
Correct Answer: B
Rationale: SGLT1 (Sodium-Glucose Linked Transporter 1) is the secondary active
transport protein on the apical (luminal) membrane of enterocytes that co-transports
glucose and sodium against the glucose gradient using the sodium gradient. GLUT2
facilitates basolateral export, while GLUT4 is insulin-dependent in muscle/adipose
tissue. [CORRECT]
Q6. A 35-year-old woman needs to increase her soluble fiber intake to help lower her
LDL cholesterol. Which food is the BEST source of soluble fiber?
A. Wheat bran
B. Oatmeal
C. Celery
D. Brown rice
Correct Answer: B
Rationale: Oatmeal is rich in beta-glucan, a soluble fiber that forms a viscous gel in
the digestive tract, binding bile acids and cholesterol for excretion, thereby lowering
LDL cholesterol. Wheat bran and celery are primarily insoluble fiber sources, while
brown rice contains moderate insoluble fiber. [CORRECT]
Q7. Which of the following is a common misconception about dietary fiber that
students should avoid?
A. Soluble fiber dissolves in water and forms a gel
B. Insoluble fiber adds bulk to stool and speeds transit
C. Fiber provides 4 kcal/g of usable energy
D. The recommended daily fiber intake is 25-38 g for adults