Question:

Which of the following statements is false?

Ca2+ions are not important in maintaining the regular beating of the heart.

Ca2+ions are important in blood clotting.

Mg2+ions are important in the green parts of plants.

Mg2+ions form a complex with ATP.

Solution:

Ca2+ ions are important in maintaining the regular beating of the heart. Ca2+ ions are also important in blood clotting and are required to trigger the contraction of muscle. Therefore, the statement 'Ca2+ ions are not important in maintaining the regular beating of the heart' is false.