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The sun radiates energy in a wide range of wavelengths, most of which are invisible to human eyes. The shorter the wavelength, the more energetic the radiation, and the greater the potential for harm. Ultraviolet (UV) radiation that reaches the Earth's surface is in wavelengths between 290 and 400 nm (nanometers, or billionths of a meter). This is shorter than wavelengths of visible light, which are 400 to 700 nm.
UV radiation from the sun has always played important roles in our environment, and affects nearly all living organisms. Biological actions of many kinds have evolved to deal with it. Yet UV radiation at different wavelengths differs in its effects, and we have to live with the harmful effects as well as the helpful ones. Radiation at the longer UV wavelengths of 320-400 nm, called UV-A, plays a helpful and essential role in formation of Vitamin D by the skin, and plays a harmful role in that it causes sunburn on human skin and cataracts in our eyes. The incoming radiation at shorter wavelengths, 290-320 nm, falls within the UV-B part of the electromagnetic spectrum. (UV-B includes light with wavelengths down to 280 nm, but little to no radiation below 290 nm reaches the Earth's surface). UV-B causes damage at the molecular level to the fundamental building block of life- deoxyribonucleic acid (DNA).
DNA readily absorbs UV-B radiation, which commonly changes the shape of the molecule in one of several ways. The illustration below illustrates one such change in shape due to exposure to UV-B radiation. Changes in the DNA molecule often mean that protein-building enzymes cannot "read" the DNA code at that point on the molecule. As a result, distorted proteins can be made, or cells can die.
But living cells are "smart." Over millions of years of evolving in the presence of UV-B radiation, cells have developed the ability to repair DNA. A special enzyme arrives at the damage site, removes the damaged section of DNA, and replaces it with the proper components (based on information elsewhere on the DNA molecule). This makes DNA somewhat resilient to damage by UV-B.
In addition to their own resiliency, living things and the cells they are made of are protected from excessive amounts of UV radiation by a chemical called ozone. A layer of ozone in the upper atmosphere absorbs UV radiation and prevents most of it from reaching the Earth. Yet since the mid-1970s, human activities have been changing the chemistry of the atmosphere in a way that reduces the amount of ozone in the stratosphere (the layer of atmosphere ranging from about 11 to 50 km in altitude). This means that more ultraviolet radiation can pass through the atmosphere to the Earth's surface, particularly at the poles and nearby regions during certain times of the year.
Without the layer of ozone in the stratosphere to protect us from excessive amounts of UV-B radiation, life as we know it would not exist. Scientific concern over ozone depletion in the upper atmosphere has prompted extensive efforts to assess the potential damage to life on Earth due to increased levels of UV-B radiation. Some effects have been studied, but much remains to be learned.
UV light can damage DNA in living organisms, potentially leading to mutations and skin cancer in humans. Overexposure to UV light can also cause sunburn and premature aging of the skin. In some cases, UV light can be used to disinfect surfaces and water by killing bacteria and other microorganisms.
UV or ultraviolet light is an ionizing form of eletro-magnetic energy at the short end (270-320nm) of the visible spectrum of light. UV light causes chemical changes to cellular structure in living cells causing damage to the DNA in pairs of thymine molecules, one of the "base links" in the DNA ladder structure. With enough damge to the DNA in the cell, it cannot carry out its proper function or reproduce and the cell dies. With enough damge to enough cells, the organism itself can die. The amount of UV light needed to damage the cell varies depending on the wavelength (short or long, also called UVC, UVB, and UVA) and the intensity. That being said, most animals require some UVA exposure to produce Vitamin D in their systems. UVC, the most harmful, from the sun is mostly filtered out by the ozone layer of our atmosphere.
It causes cell mutation, often cancer. Humans get skin cancer due to overexposure to UV radiation and try to prevent it with sun block.
Very funny u r doing ur homework that's y u want the answers research yourself
it has powerufl rays that the ozone cant pick up. they can cause skin cancer
UV radiations do harm to living organisms. UV actually depletes their population.
UV rays are high energy waves. They can cause various problems for life on earth.
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Why is ozone in the stratospere important for living things?
The ozone in stratosphere is important for living things. The living things cannot expose themselves to UV which ozone protects.
What atmospheric area is responsible for absorbing the most UV radiation?
The ozone layer high above the Earth blocks most of the ultraviolet (UV) light emitted by the Sun. This radiation is generally harmful to living things.
Is UV light the same as fluorescent light?
The UV light is different to that of fluorescent light. The UV originates from the sun. The latter one does not.No, it is not. UV is different.
How ozone effects living things?
Ozone can have both positive and negative effects on living things. In the stratosphere, it protects us from ultraviolet radiation. However, at ground level, ozone can be harmful to human health, causing respiratory issues and aggravating conditions like asthma. In plants, high levels of ozone can damage leaves and decrease photosynthesis rates.
Uv light interacts with earth surface?
Ultraviolet (UV) light interacts with the Earth's surface by being absorbed, reflected, and scattered. UV light can cause damage to living organisms, including plants and animals, depending on the intensity and duration of exposure. The Earth's atmosphere plays a crucial role in filtering out harmful UV radiation, particularly the ozone layer.
Do living things need ultraviolet light?
Some living things, like plants, require some exposure to ultraviolet (UV) light for processes like photosynthesis. However, excessive UV light can be harmful and cause damage to living organisms, including humans, by harming DNA. It is important for living things to have a balance of UV light exposure to maintain health and growth.
What gas in the atmosphere protects living things from ultraviolet light?
Ozone is the gas in the atmosphere that protects living things from ultraviolet light. It absorbs and filters out the harmful UV rays, preventing them from reaching the Earth's surface in large amounts.
How can uv light cause more than one type of effect?
UV light is a type of radiation that generally has negative consequences on living cells.
Why is the ozone layer important to all living things?
Ozone layer reflect UV radiation. UV radiation is very harmful
Why is ozone in the stratospere important for living things?
The ozone in stratosphere is important for living things. The living things cannot expose themselves to UV which ozone protects.
What atmospheric area is responsible for absorbing the most UV radiation?
The ozone layer high above the Earth blocks most of the ultraviolet (UV) light emitted by the Sun. This radiation is generally harmful to living things.
What protects living things from too musch ultraviolet radiation?
Ozone protects living things from UV rays. It is present as ozone layer.
What are Four ways that increased UV rays might affect living things?
Increased UV might affect the living things. This is by 4 ways including skin cancer, DNA affect, cataract, immune suppression.
What protects living things from to much UV rays?
The ozone layer helps us protect from too much UV rays.
Is UV light the same as fluorescent light?
The UV light is different to that of fluorescent light. The UV originates from the sun. The latter one does not.No, it is not. UV is different.
When is ozone beneficial to living things?
The ozone present at the atmospheric level is benificial to living things. It protects us from the harmful and fatal UV radiations of the sun.
What is the difference between UV light and IR light?
UV light has shorter wavelengths and higher energy than IR light. UV light is typically used for sterilization and disinfection, while IR light is used for communication, remote controls, and heating applications. UV light is also more harmful to living organisms, including humans, compared to IR light.
