Answer:
1. Given the DNA sequence: G-A-C-A-T-T-C-C-G, the complementary sequence is C-T-G-T-A-A-G-G-C (a).
2. Given the DNA sequence: G-A-C-A-T-T-C-C-G, the insertion sequence is G-A-C-G-A-T-T-C-C-G (b).
3. Given the DNA sequence: G-A-C-A-T-T-C-C-G, the deletion sequence is G-A-C-A-T-C-C-G (d).
4. Given the DNA sequence: G-A-C-A-T-T-C-C-G, the inversion sequence is G-A-C-T-A-T-C-C-G (c).
Explanation:
The complementary sequence of DNA is a sequence of complementary nucleotides. The complement is a nitrogenous base that correctly pairs with the base that is given. In DNA, Adenine (A) correctly pairs with Thymine (T), and Guanine (G) with Cytosine (C). Therefore, the complement of A is T, and of C, is G.
The given sequence complement would be C-T-G-T-A-A-G-G-C since it's a sequence of bases that correctly pairs with the given sequence, G-A-C-A-T-T-C-C-G. [ G-A-C-A-T-T-C-C-G | C-T-G-T-A-A-G-G-C ] Notice that the first base in the sequences is G and C respectively. The next two are A and T. The paring is such that C complements G, and that A, T.
2. An insertion sequence is one in which there is an extra added nucleotide or codon. [ G-A-C-A-T-T-C-C-G ] Notice that there are three Triplets in this sequence. In a case where there is an extra nucleotide(s) or codon(s), such is termed an insertion mutation. When the given sequence is compared with the sequence in option b, G-A-C-G-A-T-T-C-C-G, you can observe an extra nucleotide [G - the fourth letter in the sequence]. Therefore, this sequence is called an insertion sequence.
3. Deletion mutation is an error in the DNA replication process that removes a nucleotide(s) from the genome. Hence a sequence that has a nucleotide(s) removed from the original sequence is called a deletion sequence. With the given sequence, G-A-C-A-T-T-C-C-G, the deletion sequence to this is G-A-C-A-T-C-C-G. [G-A-C-A-T-C-C-G ] Notice that one of the nucleotides, T, is missing.
4. Inversion mutation is a chromosome rearrangement in which a chromosome is reversed end to end. This involves breaking and rearrangement within a sequence. With the given sequence, G-A-C-A-T-T-C-C-G, an inverted sequence is G-A-C-T-A-T-C-C-G. [ G-A-C-T-A-T-C-C-G] Notice the first two nucleotides, of the second codon (....-T-A-T-...). The original sequence has....-A-T-T-...., but the new sequence here has...-T-A-T-.... Suggesting that the first two nucleotides were broken and rearranged end to end.
