Nokea
Peristalsis in the muscle component of the human esophagus is produced by:
- A. A gradient in slow waves going from the top to the bottom
- B. Gravity moving swallowed food down the esophagus
- C. Simultaneous contraction of the entire longitudinal muscle layer
- D. Sequential firing of the extrinsic nerves from the nucleus ambiguous
Correct Answer: D
Rationale: Sequential firing of vagal nerves from the nucleus ambiguus coordinates esophageal peristalsis, moving food downward.
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Which body system is NOT a part of the excretory system?
- A. respiratory system
- B. digestive system
- C. circulatory system
- D. urinary system
Correct Answer: C
Rationale: The circulatory system transports substances but is not directly part of excretion.
Nutrients like calcium and zinc are often referred to as
- A. proteins
- B. minerals
- C. fats
- D. vitamins
Correct Answer: B
Rationale: Calcium and zinc are classified as minerals, essential inorganic nutrients.
Besides carbohydrates, proteins, fats, vitamins and minerals, what other nutrient does your body need for life?
- A. DNA
- B. chlorophyll
- C. water
- D. none of the above
Correct Answer: C
Rationale: Water is an essential nutrient required for all bodily functions.
A dysfunction of the parietal cells of gastric glands would result in a decreased production of which two of the following?
- A. mucus
- B. pepsinogen
- C. hydrochloric acid
- D. pepsin
Correct Answer: C
Rationale: Parietal cells secrete hydrochloric acid and intrinsic factor.
The large intestine lacks:
- A. goblet cells
- B. epiploic appendages
- C. plicae circulares
- D. haustra
Correct Answer: C
Rationale: The large intestine lacks plicae circulares, which are present in the small intestine to increase surface area.