Why are plants essential for human life

The sun of life

The entire evolution of life on earth took place under the light of the sun. It is therefore not surprising that light is essential for existence on our planet in many ways. Plants need it to generate energy through photosynthesis. They feed on sunlight, so to speak.

Not only plants need the sun to live. © Zoonar RF / thinkstock

During this process, they produce, among other things, glucose and oxygen - substances that are in turn important for many animals: the oxygen they breathe and the sugar and the carbohydrates derived from it for food. The carbon dioxide that these living things exhale is reabsorbed by the plants. This closes a cycle that is driven by the power of the sun.

Man - a being of light

A large part of the flora and fauna is therefore dependent on light in order to survive. People have been aware of this paramount importance since ancient times. Many early cultures worshiped the sun as a deity, conjured up its daily return with magical rituals and were dismayed when its light suddenly disappeared unexpectedly during a solar eclipse.

Even today, many people long for the sun, especially during the dark season. “You don't have to be esoterically irradiated to call people a light being”, the science journalist Werner Bartens once wrote in the “Süddeutsche Zeitung”.

Not just for breathing and seeing

Because people also need light indirectly to breathe - and they need it to see. When light falls through our eyes, a colorful picture of the world arises in our head. The spectrum we see from 380 to 780 nanometers in wavelength ranges from violet, blue and green to yellow and red.

But the human body also reacts sensitively to light in other things: Daylight plays an important role as a natural human clock, it stimulates the production of vital vitamins, has beneficial effects and even has an impact on our psyche and our thinking ability.

Daniela Albat
Status: 02.03.2018

2nd March 2018