A patient presents with chronically low blood calcium despite normal dietary intake. Which outcome is most likely attributable to resistance of bone cells to parathyroid hormone (PTH)?

💡 Explanation

Resistance to PTH prevents its normal action on bone, specifically stimulating osteoblasts to release factors that activate osteoclasts, thereby decreasing calcium release from bone. Because bone cannot properly respond to PTH, calcium resorption is diminished, therefore the blood calcium concentration decreases, rather than osteoclast activity being affected overall.

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