The right answers are:
A-present in eukaryotic genomes ==> Both exons and introns
B-generally absent from bacterial genomes ==> Introns
C-part of the final mRNA strand ==> Exons
D-code for an amino acid sequence ==> Exons
E-removed from initial mRNA strand prior to translation ==> Introns
F-present in the DNA used as the template for transcription ==> Both exons and introns
In the genes of eukaryotic organisms, the exons are the segments of an RNA precursor that are conserved in the RNA after splicing and that are found in mature RNA in the cytoplasm. The segments of the RNA precursor that are removed during splicing are called in opposition to introns. Exons are mainly found in messenger RNAs (mRNAs) encoding proteins. Some mRNAs may sometimes undergo an alternative splicing process in which one or more exons may be excised or some introns preserved in rare cases.
Mutations also occur because of incorrect copying of information in Mitosis.
<span>c. They can be introduced within their natural range.</span><span>
Invasive species can threaten an ecosystem and the biodiversity of the organism that exist in the present environment when the invasive species increase rapidly in number.
</span>Exotic species are a threat to biodiversity because they alter the ecosystem of that area. They share food and habitat resulting in unbalanced ecosystem. Also, habitat destruction destroys the habitat of all the life forms in that area.
