THE MOLECULAR BASIS OF INHERITANCE
DNA REPLICATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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All life-forms can reproduce with one another
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All life-forms have the same number of genes.
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All life-forms have a common evolutionary ancestor.
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All life-forms arose about the same time in Earth’s history.
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Detailed explanation-1: -The genetic code is nearly universal. That means, with few exceptions, the same codons code for the same amino acids in all organisms. What does the near universality of the genetic code suggest? All life-forms have the same number of genes.
Detailed explanation-2: -The genetic code is (nearly) universal With some minor exceptions, all living organisms on Earth use the same genetic code.
Detailed explanation-3: -With a few exceptions (some prokaryotes, mitochondria, chloroplasts), the genetic code is universal – it’s the same in all organisms from viruses and bacteria to humans. The table of the Standard Universal Genetic Code on the next page shows the RNA version of triplet codons and their corresponding amino acids.
Detailed explanation-4: -The genetic code is universal. All known living organisms use the same genetic code. This shows that all organisms share a common evolutionary history.
Detailed explanation-5: -As well as being degenerate, the genetic code is also referred to as ‘unambiguous’ which means that each possible codon can code for one amino acid only. The genetic code is almost universal (i.e. it is the same for all living organisms and in all types of DNA/RNA) however there are some exceptions.