Bio physics presentation

2. What is radiation?
• Meaning :
Emission of energy in the form of waves or particles through space or
through a material medium.
• Types:
Ionizing , non ionizing , electromagnetic , particle
• Examples:
x-Rays , Gamma , sun light
• Ionizing Vs Non ionizing

4. • Electromagnetic spectrum
• Is a model we use to understand and classify energy.
• High energy waves :
• have short wave lengths which mean their crests are close together.
• These waves go up and down frequently so they called high frequency.
• Low energy waves :
• have long wavelengths with crests which may be miles a part
• These waves go up and down slowly so they called low frequency.

5. • As the wavelengths of energy decrease and the frequencies increases the waves reach a
point where they are able to penetrate the living cells.
• This penetration ability happen in the ultraviolet region of spectrum.
• Penetrating energies are called ionizing

6. • Ionizing Disrupt living cells :
in two ways

7. • Directly ionizing energy penetrates nucleus and breaks
bonds in the DNA molecule .
• Indirectly ionizing energy breaks neutral cellular water into
several different ions and free radicals.
• These charged pieces then interact with the DNA and other
molecules to cause the damage .

8. • Low energy
• Long wavelength
• Healthy non-ionizing life-style

10. • High energy.
• Short wavelength

11. • Enjoys UV rays
• Study X-rays , gamma

12. • Electromagnetic spectrum occurs naturally , but
humans have found new ways to generate all kinds of am
radiation .

13. • Our toys and tools use electricity as their power
and convert this beam of electrons into other forms
of energy.

15. • Ultraviolet light includes both ionizing and non-ionizing
radiation.
• UV that has an energy of 10 eV or less is unable to penetrate
or damage DNA cells.

16. • UV radiation is used for medical sterilization
because it kills bacteria .

17. • Trigger cataracts.
• Cause retinal damage.

19. • Visible light includes only frequencies that can be
perceived by human eye. When these wavelengths bounce of
the surfaces , the reflected light hits our retinas ,and tells the
brain what colors we see.

20. • All normal artificial lights emit visible light.

21. • Many lasers are focused enhanced visible light.
• This non ionizing radiation is generally benign .
• But wear your sunglasses when it’s bright.

22. Stay safe

23. • Infrared is heat we know how it feels and too
much can be deadly.

24. Heat energy can be seen if you are snake or
have a special camera.

25. • Microwaves have wavelength of 1 M mm to 1
meter , They pass through matter vibrating .

26. • Heating atoms are non ionizing microwaves
but they can cause cancer even ones emitted
by cell phone.

27. • Radio waves are one meter to two kilometers
in wavelength so they usually so they go
around us rather than through us.

28. • Medicine MRIs use radio waves and magnetic
fields to create their images.
• Radio Frequency lasers used to destroy
rumors.

29. Reference:
https://www.youtube.com/watch?v=rApXQmkpK-Q