Below is the periodic table of elements. It shows all of the possible types of atoms known to exist in the universe.
Highlighted in red are the 6 most common atoms (building blocks) found in living things on Earth.
- The carbon (C) element is found in most molecules within living things.
- It is for this reason that we describe all living things on Earth as being “carbon-based”.
- In theory, we might find living things that do not consume carbon-based molecules and therefore are not carbon-based.
- Instead, they could make use of other atoms that have similar properties to carbon (highlighted in blue on the periodic table).
- Examples include silicon (Si; commonly found in sand) and germanium (Ge).