Stories by Earl Frieden

Until recently it was believed that living matter incorporated 20 of the natural elements. Now it has been shown that a role is played by four others: fluorine, silicon, tin and vanadium

Like Iron, copper is indispensable to the life processes of most animals and plants. Its chemical nature notably allows it to play a key role in the function of proteins

The evolutionary transition from fish to land animal is paralleled by the transformation of an aquatic tadpole into a frog. Essential biochemical changes accompany and implement this conquest of land

The fleeting union of the enzyme and the substance on which it acts holds a key to our understanding of life processes. Many ingenious techniques are in use today to isolate it for study