Question

It is said that elemental composition of living organisms and that of inanimate objects (like earth’s crust) are similar in the sense that all the major elements are present in both. Then what would be the difference between these two groups? Choose a correct answer from among the following:

Options

• Living organisms have more gold in them than inanimate objects

• Living organisms have more water in their body than inanimate objects

• Living organisms have more carbon, oxygen and hydrogen per unit mass than inanimate objects

• Living organisms have more calcium in them than inanimate objects

Answer 1

Living organisms have more carbon, oxygen and hydrogen per unit mass than inanimate objects

Explanation:

Element	% Weight of
	Earth’s Crust	Human Body
Hydrogen (H)	0.14	0.5
Carbon (C)	0.03	18.5
Oxygen(0)	46.6	65.0
Nitrogen (N)	very little	3.3
Sulphur (S)	0.03	0.3
Sodium (Na)	2.8	0.2
Calcium (Ca)	3.6	1.5
Magnesium (Mg)	2.1	0.1
Silicon (Si)	27.7	negligible