15. skin care COPY Flashcards
What is a free radical?
A species ( atom or group of atoms) with an unpaired electron
What causes free radical formation in the atmosphere?
UV light
What is meant by “homolytic fission” of a covalent bond?
When both atome leave with one electron each from the bond.
What type of covalent bonds are likely to break by homolytic fission?
Non-polar bonds where each atom has a similar electronegativity
What can cause free radical formation oin the body?
What are the 3 steps in a free radical chain reaction?
- Initiation
- Propagation
- Termination
Which step is shown below?
Initiation
Which step is shown below?
propagation (step 1)
What step is shown below?
propagation (step 2)
What steps are shown below?
Termination
what are the 2 ways that sun creams work?
How do free radicals scavengers work?
- Donating electrons to free radical
- form covalent bonds with free radical
What do some skin creams contain to help combat free radical damage?
Free radical savengers
