Answer:
Thymidine dimers is likely to be repair as soon as it is originated but if left unrepaired then it causes frame shift mutations.
Explanation:
In case of Bacterium if UV irradiation induces covalent linkage of two thymidine present adjacently to each other or on a single strand to make thymidine dimers.
These either excised via DNA repair enzyme like Endonuclease V and the proof reading activity of DNA polymerase I enzyme help in incorporation of nucleotide by taking the unmutated original strand as a template.
These dimers if not excised before second round of replication than the sequence of newly synthesized strand will be altered. As DNA polymerase III enzyme read thymidine dimers as single thymidine nucleotide and incorporate only 1 adenine in the newly synthesizing complementary strand which results in frame shift mutations
It is the mutation in which reading frame of codons is shifted or altered due to deletion or addition of a single nucleotide.
The invading bullfrogs ARE HARMFUL. This is because, they cause decline in the population of the native species.
Decline in the population of the native species will throw the ecosystem into a condition of imbalance which will eventually affect all the living organisms that are living in that ecosystem.
