What happens to oxygen during the end of the transport chain

If the coding part of an mrna molecule is 1800 nucleotides (bases) in length, this molecule will contain codons and code for a polypeptide that is amino acids long.

With the word calcite wich completes the analogy mineral, erosion, marble, or aragonite

Which best describes a gene? a. a sister chromatid b. a chromosome c. a tetrad d. a piece of a chromosome