THE MOLECULAR BASIS OF INHERITANCE
DNA MAKES RNA MAKES PROTEIN
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[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Detailed explanation-1: -A codon is a DNA or RNA sequence of three nucleotides (a trinucleotide) that forms a unit of genomic information encoding a particular amino acid or signaling the termination of protein synthesis (stop signals). There are 64 different codons: 61 specify amino acids and 3 are used as stop signals.
Detailed explanation-2: -Three codons, UAA, UAG, and UGA, are known as stop codons as they stop the process of translation. If this is a mutation as a stop codon and its finishes prematurely it is called an amber codon. AUG is also known as a start codon, as it initiates the process of translation.
Detailed explanation-3: -Three is the minimum number of nucleotides per codon needed to encode 20 amino acids.
Detailed explanation-4: -Answer and Explanation: Codons must consist of three nucleotides because this gives the cell the appropriate amount of combinations to code for all twenty amino acids with some redundancy. There are four possible bases in DNA. So, if each codon was only one nucleotide, we could only code for four amino acids.
Detailed explanation-5: -Multiple codons can code for the same amino acid. The codons are written 5’ to 3’, as they appear in the mRNA. AUG is an initiation codon; UAA, UAG, and UGA are termination (stop) codons.