The document discusses ultraviolet (UV) radiation from the sun. It notes that UV radiation is found in sunlight and is a form of electromagnetic radiation with shorter wavelengths than visible light. While UV radiation can be beneficial in moderating amounts, overexposure can cause skin cancer and other health issues. The document provides information on sources of UV radiation besides the sun, as well as the effects of UV on the ozone layer and how to reduce risks from UV exposure like sunburn and skin cancer.

1. RAD IA TI ON AND LIFE MODULE P2 www.sciencetutors.zoomshare.com

2. On Earth, sunlight is filtered through the atmosphere, producing radiant heat and Ultra-Violet (UV) radiation SUN LI G H T www.sciencetutors.zoomshare.com

3. SUN LI G H T Most energy from the Sun is in the form of visible and UV radiation. www.sciencetutors.zoomshare.com

4. UV RADIATION UV radiation or ultraviolet rays is a form of energy traveling through space. The sun is our primary natural source of UV radiation. OTHER SOURCES OF UV RADIATION Curing Lamp Mercury Vapour lamps Halogen lamps Tanning booths www.sciencetutors.zoomshare.com

5. BASIC FACTS ABOUT UV RA DI AT IO N UV light is found in sunlight UV light is electromagnetic radiation. The wavelength of UV radiation is shorter than that of visible light, but longer than x-rays. The shorter the wavelength of UV, the more biologically damaging it can be if it reaches the Earth in sufficient quantities UV radiation is both beneficial and damaging, on human health. www.sciencetutors.zoomshare.com

6. UV RADIATION Ultraviolet radiation (UV) is more energetic than visible radiation and therefore has a shorter wavelength. www.sciencetutors.zoomshare.com

7. BINGE SUN BATHING Survey shows that short, intense exposure to the sun in much hotter climate doubles your chances of getting the most fatal of skin cancer. TRUE OR FALSE ? And Why? www.sciencetutors.zoomshare.com

8. Overexposure to ultraviolet radiation (UV), can cause skin cancer and other serious health effects. Your Task Make a list of health problems caused by UV Acknowledgement of photo copied from www.supanet.com www.sciencetutors.zoomshare.com

9. UV radiation is both Beneficial and Damaging to Human. Class to discuss and note down answers using bullet points BENEFITS AND RISKS www.sciencetutors.zoomshare.com

10. 3 Minutes Task Describe at least any 3 ways that a person can reduce sunburn and the risk of skin cancer. Sunburn Skin cancer www.sciencetutors.zoomshare.com

11. Discuss and write down simple guidelines you can follow to protect against damage from the sun's harmful rays. Acknowledgement of photo copied from www.supanet.com www.sciencetutors.zoomshare.com

12. SUNLIGHT AND LIFE www.sciencetutors.zoomshare.com Why Do Plants Have Leaves?

13. Input And Out Energy In Photosynthesis www.sciencetutors.zoomshare.com PHOTOSYNTHESIS Input Energy comes from the light absorbed by the leaves Output Energy is provided by Respiration when starch is used up.

14. SUNLIGHT ENERGY & SELECTIVE ABSORPTION www.sciencetutors.zoomshare.com What is selective Absorption? Leaves absorb the red and blue light from sunlight when it falls on leaves but reflect other colours-This process is called selective absorption

15. What do plants use sunlight Energy for? www.sciencetutors.zoomshare.com For Photosynthesis To combine water and carbon dioxide To make starch ( Carbohydrate ) and release oxygen

16. www.sciencetutors.zoomshare.com A layer in the Earth's atmosphere that contains relatively high concentrations of ozone ( often written as O 3 ) is called OZONE LAYER OZONE OR O 3 LAYER

17. www.sciencetutors.zoomshare.com FACTS ABOUT OZONE OR O 3 LAYER In the upper atmosphere, some of the oxygen is in the form of ozone. Each molecule of ozone has three oxygen atoms and is produced when oxygen molecules (O2) are broken up by energetic electrons or high energy radiation. Well over 90% of the earth's ozone resides in the stratosphere. Ozone is colourless, Irritating and corrosive Ozone is good at absorbing UV radiation and absorbs about 93-99% of the sun’s UV

18. What effect do UV radiation have on Ozone? 3 Atoms of Oxygen in Ozone molecule

19. What effect do CFCs have on Ozone 3 Atoms of Oxygen in Ozone molecule

20. What action do we need to take to reduce damage to the ozone layer? 3 Atoms of Oxygen in Ozone molecule

21. GLOBAL WARMING www.sciencetutors.zoomshare.com CLIMATE CHANGE

22. EM RADIATION Homework Task What are ions? What is ionization? Research on the following – Photons, Ionizing radiation, Non-Ionizing radiation, Examples of Ionizing and non-ionizing radiation.

23. MOBILE PHONES - COOKED BRAIN? Are Mobile Phones Safe? How safe are Mobile Phones? Class to discuss and note down answers . Homework What are the actual risk and perceived risk of using mobile phones www.sciencetutors.zoomshare.com

24. TYPES OF RISK www.sciencetutors.zoomshare.com Actual Risk Perceived Risk

25. BINGE SUNBATHING FACTS Young people are mostly at risk of binge sunbathing as it increases the risk of skin cancer when older. Sunburn doubles the risk of skin cancer Melanoma is the third most common cancer among people age between 15-39. Many skin cancers start with the development of, and changes in, moles. Freckles develop often develop if you spend a lot of time in the sun.