Answer:
A codon is found on the coding strand of double-stranded DNA and in the (single-stranded) mRNA. The anticodon is found on the tRNA and is the part that base-pairs with the codon (on the mRNA) in order to bring the appropriate amino acid to the ribosome to be added to the growing peptide chain.
Answer/Explanation:
The DNA in all living organisms is made up of 4 bases, adenine, thymine, guanine, cytosine. The RNA replaces thymine with uracil, making 5 types of nucleotide. The number of nucleotide pairs in a genome can range from half a million up to 100,000 million - meaning there are an exponential number of combinations of these 4 bases.
Imagine an organism exists that has only 2 nucleotides (<u><em>this is over 200,000x smaller than even the smallest bacterial genome</em></u>). If we allow any nucleotide at each of the 2 positions, then we have 4x4 (4²) or 16 possible combinations of sequences. For a nucleotide length of 4, the total number of possible combinations are 4⁴ or 256.
Since we are dealing with many millions of nucleotides, there are essentially infinite combinations of nucleotides, giving rise to the variation that produces over 20 million organisms on the planet.
<span>This barrier is known as reproductive isolation and and generally occurs when two species have incompatible genitalia which are unable to function together. It can also occur when the sperm of the male species is unable to be fertilized by the female, regardless of genital compatibility.</span>