Answer:
Codon transcription
Explanation:
The DNA, present in the nucleus, is the stored form of the genetic material i.e. a segment of it is called a gene. DNA is one of the two types of Nucleic acids made up of nucleotide sequences. A nucleotide is a combination of a five-carbon sugar (Deoxyribose in DNA), nitrogenous base and a phosphate group. These nucleotides are arranged in sequence to form the nucleic acid (DNA or RNA).
The information stored in this gene has to be expressed, and this is done via transcription and translation processes.
Transcription is the transfer of genetic instructions in DNA to mRNA. In transcription, a strand of mRNA that is complementary to a strand of DNA is formed. Transcription occurs in three steps viz: Initiation, elongation and termination where RNA polymerase uses sequence of bases in DNA to make a complementary strand of mRNA. The mRNA undergoes additional processing including spicing, editing and polyadenylation before it leaves the nucleus to the ribosome for protein synthesis.
Each three successive nucleotide base stretch of mRNA is known as CODON and each coding contains information for a specific amino acid. These codons direct protein synthesis with assistance of tRNA in a process called translation.
In translation, the mRNA sequence is used as a template to assemble, in order, the chain of amino acids that form a protein.
If there is a change in the nucleotide sequence in the gene (segment of DNA), it will lead to a change in the sequence of the three-base mRNA (codon) formed, which may ultimately cause a change in sequence of amino acids (proteins)
Answer: DNA.
Explanation:
Based on structure a part of DNA molecule contains sequence of nucleotide which codes for just one polypetide.This part of the DNA molecule is called a GENE. An alteration in this sequence of nucleotide of a gene, results in change in arrangements of polypeptide; this is called MUTATION. Therefore a change in the nucleotide sequence of a gene will affect the DNA. Since the DNA codes for protein sequence and expression the AMINO ACID SEQUENCE will be affected
