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i) Sudden change in the structure of DNA at a particular locus/chromosome/genes
ii)Mutations arise due to alterations in normal number of chromosomes,
change in a portion of a chromosome affecting one or more genes
by chromosomal aberration e.g. deleltion/duplication/substitution/inversion/translocation/crossing over
caused by mutagenic agents e. g. radiation (x-rays, ultra violet light, gamma rays) and chemicals e. g. mustard gas/colchicines.
iii) These are chemicals and radiations
a) Radiations Effects
X-rays gene/chromosome alteration
Ultra violet rays structural distortion of DNA
b) Chemicals Effect
colchicines prevents spindle formation
Cyclamate chromosome aberrations
Mustard gas chromosomes aberrations
Nitrous acid adenine in DNA is deaminated so behaves like guanine
Acridone orange addition and removal of bases of DNA
Formaldehyde
iv)a)arise suddenly
b) Are unpredictable
c) Random
d) Generally rare
e) Some are desirable while others are lethal
Anganifelix answered the question on April 17, 2018 at 12:04
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