Question

The given table shows the result of intravenous injection of substances to determine the effect of each substance on normal body variables. An appropriate amount of time was allowed between injections and the substances did not interfere with one another.

Variable	Baseline values	Values after injecting substance A	Values after injecting substance B	Values after injecting substance C	Values after injecting substance D
Serum ${Ca}^{++}$	2.3mmol/L	2.3mmol/L	2.3mmol/L	3.0mmol/L	2.3mmol/L
Serum ${Na}^{+}$	135mmol/L	135mmol/L	135mmol/L	136mmol/L	135mmol/L
Serum glucose	5.6mmol/L	3.3mmol/L	5.6mmol/L	7.4mmol/L	5.6mmol/L

The normal release of substance D will be

• A. Soon after a meal.
• B. When blood pressure is low.
• C. Between meals.
• D. When there has been limited intake of dietary calcium.
• E. When dietary calcium is in excess.

Answer 1

The correct option is B When blood pressure is low.

After intravenous injection of substance D, it is seen that there is no change in the baseline values of calcium, sodium and glucose level. When the blood pressure is low it will be released, so that the blood pressure is maintained by regulating sodium, calcium and glucose level.

So, the correct answer is option B.