RADIATION AND LIFE

THE CARBON CYCLE:

1) carbon dioxide is taken by plants for photosynthesis, and then are made into carbohydrates.

2) plants release the CO2 through respiration.

3) the carbon dioxide is taken by the plants and animals eat them.

4) plants AND animals release CO2,

5) when the animals and plants die, they decompose and microbes feast on the remains.

6) these microbes then continue to release CO2.

SOURCE- ABSORB-DETECTOR

SOURCE-REFLECT-DETECTOR

SOURCE-TRANSMIT-DETECTOR

FREQ    WAVE LENGTH     USES               ABSORBED BY:

RADIO WAVES -     LOW-         BIG           tv/radio transmitter     --------------------

MICROWAVES                                           phones/microwaves-  water molecules

INFRARED                                                 remote control-      green house gases

VISIBLE LIGHT                                          sight                        film/eye                 

ULTRA VIOLET                                     tanning/detecting forgery- ozone/suncream

X-RAYS                                                  sterilising/radiotherapy-    x-ray film           

GAMMA RAYS-       HIGH-       SHORT     sterilising/radiotherapy- thick lead          

INTENSITY OF RADIATION

when a body absorbs radiation, the amount of heat it gains depends on the intensity and the time of exposure.

intensity-

 number of photons

time

ALARA principle: as low as reasonably achieved.

PRECAUTIONARY PRINCIPLE: better safe than sorry.

ionoisation-increases risk of cell mutation.(cancer)