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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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.
Duodenum has characteristic Brunner's glands which secrete -
- A. Estrogen
- B. Prolactin, parathormone
- C. Estradiol, progesterone
- D. Alkaline secretion
Correct Answer: D
Rationale: Brunner's glands secrete an alkaline mucus to neutralize acidic chyme from the stomach.
The diagram shows a section through a villus. Y X What is a function of structure X and of structure Y?
- A. X: to absorb amino acids, Y: to digest starch
- B. X: to carry blood, Y: to secrete mucus
- C. X: to transport fats, Y: to secrete enzymes
- D. X: to transport glucose, Y: to help peristalsis
Correct Answer: A
Rationale: Structure X (epithelial cells) absorbs amino acids, while structure Y (goblet cells) secretes mucus.
Match each term with the correct description: filtering units of kidney
- A. urethra
- B. nephrons
- C. bladder
- D. kidneys
Correct Answer: B
Rationale: Nephrons are the filtering units within the kidneys.
Glycogen is stored in-
- A. Blood
- B. Liver
- C. Lungs
- D. Kidney
Correct Answer: B
Rationale: Glycogen is primarily stored in the liver.