L1 /
4
CH3041
OZONE LAYER III
• In the upper atmosphere
the UV-C is filtered out
by ionising the atoms
and molecules which are
present eg. O ® O+ + e-
the UV-C is filtered out
by ionising the atoms
and molecules which are
present eg. O ® O+ + e-
• The UV-B is primarily
filtered out through
reactions involving the
formation & destruction of O3.
filtered out through
reactions involving the
formation & destruction of O3.
• High energy photons cause
mutations in DNA eg 2 adjacent
Thymine bases dimerise in the
same strand to form a
mutations in DNA eg 2 adjacent
Thymine bases dimerise in the
same strand to form a
150
100
50
(km)
(km)
200
250 300 350
(nm)
UV-A
UV-B
UV-C
Stratopause
SUGAR
