Answer:
False. There are 20 amino acids, but 64 possible codons.
Explanation:
Genetic information for the aminoacids assembly during the protein synthesis is stored in short sequences of three nucleotides named codons in the mRNA. Each of the codons represents one of the 20 amino acids used to build the protein. The total number of possible codons is 64, from which 61 codify amino acids -more than one codon codify for the same amino acid-. One of these amino acids is also the start point of protein synthesis. And the left three codons are stopping translation points.
The codons indicating the initiation or stop points during the translation process are:
• The start codon AUG is the most common sequence used by eukaryotic cells and places near the 5´extreme of the molecule. However, other codons might be used as well. Prokaryote cells might use the codons GUG or UUG.
• The end codons are UAA, UAG, UGA.
A substance that tends to reduce the surface tension of a liquid in which it is dissolved (took that right from dictionary.com)
Answer:
A mutation in <u>DNA </u>results in a change in <u>RNA </u>that sometimes produces a <u>protein </u>with altered structure and function.
Explanation:
DNA is the hereditary material which causes gene expression in our body by producing protein. The type of protein which is produced by DNA totally depends upon the sequence of nucleotides in the DNA. But, DNA molecule does not produce protein directly. Initially it produces RNA (mRNA, tRNA, rRNA) by the process of transcription, the nucleotides in the RNA are complimentary to those in DNA. In short, the message regarding the structure and composition of the type protein to be produced by DNA is first decoded from DNA in the form of RNA. These RNA molecules then synthesize the protein as per the instructions from DNA by the process of translation.
But, in case a mutation occurs in the DNA which causes a change in it's nucleotide/nucleotides, the protein which will be produced will be different in the structure and function than the protein which was supposed to be synthesized. It happens because, a triplet of nucletiodes in the DNA and hence RNA specifies a particular type of amino acid and several amino acids are joined in a long chain to form polypeptide which ultimately forms protein. But, if any nucleotide in the triplet is changed due to mutation it may change the amino acid and if amino acid will change the protein will also get altered.