Question

Which of the following are not the effects of Parathyroid hormone?

1. Stimulates the process of bone resorption,
2. Decreases Ca²⁺ level in blood,
3. Reabsorption of Ca²⁺ by renal tubules,
4. Decreases the absorption of Ca²⁺ from digested food,
5. Increases metabolism of carbohydrates.

Choose the most appropriate answer from the options given below

• A. (a) and (c) only
• B. (b), (d) and (e) only
• C. a) and (e) only
• D. b) and (c) only

Answer 1

The Correct Option is B

To determine the effects of Parathyroid hormone (PTH), we evaluate each given option:

1. Stimulates the process of bone resorption: PTH increases the activity of osteoclasts which breaks down bone tissue, releasing calcium into the bloodstream. This is a known effect of PTH.
2. Decreases Ca²⁺ level in blood: PTH actually increases calcium levels in the blood by stimulating bone resorption, enhancing renal reabsorption of calcium, and increasing intestinal absorption of calcium. Thus, this statement is not an effect of PTH.
3. Reabsorption of Ca²⁺ by renal tubules: PTH promotes renal calcium reabsorption, thus conserving calcium levels. This statement aligns with known PTH effects.
4. Decreases the absorption of Ca²⁺ from digested food: PTH increases calcium absorption from the intestine indirectly by promoting the formation of active vitamin D (calcitriol). Therefore, this is not an effect of PTH.
5. Increases metabolism of carbohydrates: PTH does not primarily influence carbohydrate metabolism. This is not a known effect of PTH.

Based on the analysis, the statements that are not effects of PTH are:

1. (b) Decreases Ca²⁺ level in blood
2. (d) Decreases the absorption of Ca²⁺ from digested food
3. (e) Increases metabolism of carbohydrates

The correct option is: (b), (d) and (e) only