The periodic table of the elements with the most common elements within living cells highlighted.
Click on image for full size
L.Gardiner/Windows to the Universe

The Elements of Life

Elements make up everything around us including the trees of a forest, your pets, and even YOU!

If you looked at living things with a microscope, you would see that all life is made up of small compartments called cells. Very small life forms, such as bacteria, have only one cell, while large animals have millions. No matter what type of living thing, the cells of every creature are made of atoms of different elements.

The most common elements in a cell are:
Hydrogen (H) 59%
Oxygen (O) 24%
Carbon (C) 11%
Nitrogen (N) 4%
Others such as phosphorus (P) and sulphur (S) 2% combined

But these are not the only elements that have important roles for living things! Plants and animals need a variety of elements to survive and grow.

Some elements that are important for animals (including people) are calcium (Ca), for bones and muscles, chlorine (Cl) for digesting food, fluorine (F) for tooth enamel and iron (Fe) to help blood carry oxygen around the body.

Plants also need elements to survive and grow including magnesium (Mg) and chlorine (Cl) that help plants convert the Sun’s energy into food. Some plants, such as grass, contain silica (Si), which makes them very strong.


Last modified July 7, 2004 by Lisa Gardiner.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

The Periodic Table of the Elements

Everything you see around you is made of tiny particles called atoms. There are many different types of atoms, each with a special combination of protons , neutrons and electrons . These different types...more

Element (Chemical Element)

An element (also called a "chemical element") is a substance made up entirely of atoms having the same atomic number; that is, all of the atoms have the same number of protons. Hydrogen, helium, oxygen,...more

Kingdom Plantae

Kingdom Plantae contains almost 300,000 different species of plants. It is not the largest kingdom, but it is a very important one! In the process known as "photosynthesis", plants use the energy of the...more

Photosynthesis

Photosynthesis is the name of the process by which autotrophs (self-feeders) convert water, carbon dioxide, and solar energy into sugars and oxygen. It is a complex chemical process by which plants and...more

What’s That Mineral?

Spotting minerals is fun! There are many different types of minerals, each with a different name and a special set of characteristics. So, if you find a mineral that you do not recognize, you can use...more

Quartz

Quartz is one of the most common mineral in Earth’s crust! Silica (Si) and Oxygen (O) are the only elements within pure quartz. If a cooling magma has silica leftover after feldspars form, quartz is likely...more

Mica Minerals

Mica minerals make some rocks sparkle! They are often found in igneous rocks such as granite and metamorphic rocks such as schist. They sparkle because light is reflected on their flat surfaces, which...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA