Question

Frameshift mutations are caused by
(A) Inversion and translocation
(B) Deletion and insertion
(C) Deletion and transversion
(D) Insertion and inversion

Answer 1

Hint: Frameshift mutations mean a change of a single nucleotide sequence that may be due to insertion of nucleotide or deletion of nucleotide.
Step by step solution
The mutation which results in the alteration of DNA sequences leads to changes in the genotype of an organism which will automatically reflect the change in the organism.
Mutations also arise due to changes in a single base pair of DNA. This type of mutation is known as a point mutation. A very famous example of point mutation is sickle cell anaemia.
Deletions of base pair of DNA and insertions of base pairs of DNA leads to a frameshift mutation.
Chemical and physical factors that induce mutations are known as mutagens, examples such as UV radiation can cause mutations in organisms therefore it is a mutagen.
Some abnormalities caused by deletion or insertion that are due to frameshift mutation are Crohn's disease, cystic fibrosis, and certain types of cancer.
Therefore, the correct answer is option (B), which is due to insertion and deletion
Note We have discussed above that mutations are also a cause of variations, but you must note that recombination is a continuous source of variation that no matter what this process always occurs during the meiosis of a normal cell cycle whereas on the other hand mutation is a chance event though it also leads to variations among generations. The mutation is a discontinuous and jerky process. Single step large mutation is known as saltation and this leads to speciation in the formation of new species.