Nokea
Starch is digested to maltose by the enzyme amylase. According to the 'lock and key' hypothesis, which is the 'key' and which is the 'lock'?
- A. key: amylase, lock: starch
- B. key: starch, lock: amylase
- C. key: maltose, lock: amylase
- D. key: amylase, lock: maltose
Correct Answer: A
Rationale: In the lock and key model, the enzyme (amylase) is the key that specifically binds to the substrate (starch), acting as the lock.
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Hyperthermic means:
- A. Too cold
- B. Normal
- C. Too hot
- D. Stable
Correct Answer: C
Rationale: Hyperthermic refers to an abnormally high body temperature.
Neck of fundic [gastric] gland contain the following except:
- A. Mucous neck cells
- B. Paneth cells
- C. Parietal cells
- D. Stem cells
Correct Answer: B
Rationale: Paneth cells are found in the small intestine, not in gastric glands; the neck contains mucous neck cells, parietal cells, and stem cells.
Which of the following describes one function of the stomach?
- A. To introduce carbohydrates to food.
- B. To remove excess water from food.
- C. To temporarily store food.
- D. To absorb nutrients into the bloodstream.
Correct Answer: C
Rationale: The stomach temporarily stores food, mixing it with gastric juices for digestion.
What role does the stomach play in the maintenance of normal vitamin B12 levels?
- A. Produces intrinsic factor
- B. Absorbs vitamin B12
- C. Stores vitamin B12
- D. Converts vitamin B12
Correct Answer: A
Rationale: The stomach's parietal cells produce intrinsic factor, necessary for vitamin B12 absorption in the ileum.
About filiform papilla all true except:
- A. Secondary papillae extend from the primary papillae. Each one has a separate epithelial cap
- B. Found on the anterior two thirds of the tongue in oblique transverse rows
- C. Less numerous than fungiform papilla
- D. No taste buds in filiform papillae, but they contain nerve endings for touch.
Correct Answer: C
Rationale: Filiform papillae are the most numerous type on the tongue, not less numerous than fungiform papillae, and they lack taste buds.