Why do we need sunlight?

Answer 1

Firstly, I believe the question is somewhat misstated, given that function implies design intentions. Nonetheless, the Sun provides energy to the Earth through radiation generated at its core via nuclear fusion processes. This energy arrives at Earth across the electromagnetic spectrum, but we perceive a small part of it as visible light.

For one this energy warms the planet. Without it, the temperature would be about the freezing temperature of water - dramatically changing the form of life that could exist.

For another, this energy is absorbed by autotrophs (plants) and used as part of photosynthesis to create ATP (cellular energy). The existence of plants allows for more complex organisms to be supported, and ultimately support nearly all ecosystems on Earth.

Lastly, the Sun powers solar calculators.

Answer 2

Two reasons we need sun are to live if their was no sun the earth would start to freeze. We need sun (vitamin D) to actually live. Also we need the sun to have day and night if there was no sun the earth would be cold and dark. Also human life will sease to EXSIST!!!!!!

A:

The sun is possibly the most important factor that makes life on earth possible. It is the sole provider of the energy that sustains life on earth. The energy from the sun is used by the plants to grow which in turn support all other life on earth and allow us to have oxygen to survive.

Another extremely important reason is that without the sun, the temperatures on earth will be extremely cold that nothing will survive. Water will only exist as ice thus making life impossible.

And this is just a scratch at the surface of the many many reasons why we need the sun.

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Even more fundamentally, without the Sun there'd probably be no Earth!

Answer 3

Although too much sunlight can damage our cells, limited exposure to sunlight can be beneficial. when exposed to ultraviolet radiation, cells in the body convert cholesterol-related steroids to vitamin D. The liver then converts the vitamin D into a product that the kidney uses to help with absorption of calcium and phosphorus, and from that leads to impaired bone maintenance and growth.

Answer 4

When you say "function", do you mean a purpose or a reason for the sun ?

The only statement we can recall that gave a purpose for the sun came from

Genesis, where it states that the sun was created to give light, and placed in

the sky to rule the day.

Answer 5

An answer to that could be long and complex. In short we need it for heat and light, to help things grow, to affect our climate, for energy and to sustain life in many other ways. Without the sun the planet would not survive for these and other reasons.

Answer 6

The sun provides the means necessary for many producers to make food for themselves and other organisms living in the oceans.

Answer 7

With out the heat of the Sun there would be no life on Earth.

Answer 8

It would be pretty cold without it!!