P3 - X Rays Flashcards
What is the size of an X Rays wavelength?
X Rays have the wavelength about the size of a diameter of an atom.
Give some applications of X Rays
Medicine
Checking Structures
Security (eg. at airports)
Why are X Rays dangerous?
X rays are ionising. Repeated exposure can cause mutations in cells and possibly lead to cancers.
This effect is worse in young people as their cells are rapidly dividing.
Why should pregnant women not have X Rays?
X Rays are ionising
Rapidly developing cells are easily affected
Could cause mutations and cancers.
What precautions can be taken against X Rays?
Wearing badges which show how much exposure you have had to them.
Wear aprons lined with lead as lead absorbs X Rays.
Stand behind a screen with lead lining.
How do X Rays interact with tissues and bones?
X rays get transmitted through the soft tissues and the skin. Bones absorb the X rays because they are more dense. The X Rays get through cracks in the bones and hit the photographic film which then turns it black. You can then spot where any cracks and breaks are.
Only a 2D image is produced.
How can we see some soft tissues?
Patients can drink a contrast medium which is a drink denser than skin which will absorb the x ray.
How can X rays be used to treat patients?
X rays can be used to kill tumours and cancer cells. I works by targeting the tumour with the x rays. The x ray beam is rotated around the body so only the cancer cells are constantly exposed.
What is a CT scanner?
A CT scanner produces a digital image of any cross section in the body. It takes many pictures to give a 3D image. However, this procedure costs more and the patient is subjected to more x rays.
