Biochemical Evidence of Common Descent

Throughout the history of life on earth, every living organism on earth has been made of the same basic ingredients.

The common make up of all organisms supports the theory that all living organisms throughout history shared a common ancestor 3.5 million years ago.

The Six Most Common Elements in Living Organisms

There are six elements found in all living organisms.These elements combine in predictable ways, creating the four macromolecules of life.

Do you want to remember all six elements? Just remember their letters from the periodic table: C, H, O, N, P, S

These elements are constantly recycled through the earth's biosphere - passing between living (biotic) and non-living (abiotic) things.

Structure of water

The Macromolecules of Life

Most living organisms on earth are composed of four essential macromolecules: carbohydrates, proteins, lipids and nucleic acids.

Nuclei acids - such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)
Proteins - such as hormones, enzymes (such as polymerase), and the amino acidsthat make up proteins
Lipids (fats) -such as cholesterol
Carbohydrates - such as glucose and cellulose