BOTANY Higher Secondary Second Year - Textbooks Online

has been extensively used for inducing mutations in microorganisms, higher
plants and animals.
Significance of mutation
Mutations play an important role in the origin of new species and
serves as a tool for evolution.
Induced mutations are useful in agriculture, animal husbandry and
biotechnology to produce new strains. For example, mutant strains
of Penicillium produces more penicillin.
It is one of the best approaches for improvement of crops.
Induced mutants are reported in paddy, wheat, soyabeans, tomatoes,
oats, and barley. Mutant varieties of wheat are early maturing, disease
resistance and they are enriched with protein. Mutant varieties of
paddy produce many tillers with long grains.
The study of mutant strains of viruses helps us to know the fine
structure of gene. The genes are made up of small functional units
such as cistron, recon and muton. Cistron is an unit of function,
recon is the unit of recombination and muton is the unit of mutation.
Many types of mutations cause heritable diseases and cancer in human
beings.
Self evaluation
I . Choose and write the correct options.
1. Hugo de Vries first used the term mutation based on his
observation on
a. Sorghum b. Neurospora
c. Oenothera lamarckiana d. Cicer gigas
2. Biochemical mutants of _____ failed to synthesize certain amino
acids.
a. Sorghum b. Neurospora
c. Cicer arietinum d. Cicer gigas
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