What holds a protein in its tertiary structure?
A. Weak chemical bonds between widely spaced amino acids
B. Disulfide bonds between sulfur groups on cysteines
C. Hydrogen bonds between nearby amino acids
D. Both weak chemical bonds between widely spaced amino acids and disulfide bonds between sulfur groups on cysteines are correct.
Answer: D
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Simple mastectomy for breast cancer involves removal of:
A) all breast tissue and the underlying muscles. B) the nipple and areola. C) only one breast quadrant. D) all breast tissue superficial to the retromammary space. E) all of the lymph nodes that drain the breast.
Mrs. Wong goes to the emergency room with the following symptoms:
severe pain in the umbilical region, loss of appetite, nausea, and vomiting. While she was waiting to see a doctor, the pain moved to the lower right abdominal quadrant. What is the likely diagnosis and treatment? What will be an ideal response
In the nephron loop,
A) active secretion of acids, ammonia, and drugs occurs. B) ion pumps, which respond to aldosterone, exist. C) reabsorption of ions, amino acids, water, and other organic nutrients is its primary function. D) two-thirds of the sodium and chloride ions remaining in the tubular fluid are reabsorbed. E) final adjustments are made in the composition and concentration of the tubular fluid.
Which of the following is not true of parietal cells?
A) They contain carbonic anhydrase that converts carbon dioxide and water into carbonic acid. B) They produce bicarbonate by dissociation of carbonic acid. C) They import chloride ions from the interstitial fluid to produce hydrochloric acid in the gastric glands. D) They release bicarbonate into the lumen of gastric glands. E) They release bicarbonate into the interstitial fluid that then enters the bloodstream.