The basic structure of proteins is quite simple: they are formed by hooking together in a chain discrete subunits called amino acids.

Thus it seemed to Haeckel that such simple life could easily be produced from inanimate material.

It was only about sixty years ago that the expansion of the universe was first observed.

In order to say that some function is understood, every relevant step in the process must be elucidated.

In many biological structures proteins are simply components of larger molecular machines.

In the 19th century the anatomy of the eye was known in great detail and the sophisticated mechanisms it employs to deliver an accurate picture of the outside world astounded everyone who was familiar with them.

The basic structure of proteins is quite simple: they are formed by hooking together in a chain discrete subunits called amino acids.