Question

The given table shows the result of intravenous injection of substances to determine the effect of each substance on normal body variables. 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	138mmol/L
Serum glucose	5.6mmol/L	3.3mmol/L	5.6mmol/L	7.4mmol/L	5.6mmol/L

Which one of the following change in variable values is insignificant?

• A. The change in serum glucose when substance A is injected.
• B. The change in serum ${Na}^{+}$ when substance D is injected.
• C. The change in serum ${Ca}^{++}$ when substance C is injected.
• D. The change in serum glucose when substance C is injected.
• E. The change in serum ${Na}^{+}$ when substance B is injected

Answer 1

The correct option is E The change in serum ${Na}^{+}$ when substance B is injected

The process by which the human body controls the internal ennvironment is known as Homeostasis . The addition or presence of any variable tends to regulate the concentration of any substance or body temperature towards a constant. examples of this homeostasis is seen in Human body wherein there is a regulation of the body temperature, concentration of Na+, Ca++ ions and glucose levels in blood plasma. According to the given table showing the intravenous injection of substances to determine the effect of each substance on normal body variables, the change in serum Na+ when substance B is injected is insignificant.