For example, by random folding, the amino-acid chain of the enzyme ribonuclease, a small protein, could adopt more than 1040 different shapes, which would take billions of years to explore.

• 例如，通过随机折叠，核糖核酸酶（一种小型蛋白质）的氨基酸链能形成超过1040种不同的结构，单这一种蛋白质就需要数亿年的时间来探索。