<span>An
atom with an atomic number of 12 has 12 protons. Because the mass
number is the sum of the protons and neutrons, the mass number would
need to be at least 12. I hope this helped!
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The process of RNA editing is the alteration of the sequence of nucleotides in the RNA after it has been transcribed from DNA, but before it is translated into a protein. RNA editing occurs by two distinct mechanisms:<em><u /><u>Substitution</u> <u>editing </u></em>and <u><em>Insertion/</em></u><em></em><u><em>deletion</em></u><em> <u>editing</u></em>.
<u><em>Substitution editing</em></u> is the chemical alteration of individual nucleotides. These alterations are catalyzed by enzymes that recognize a specific target sequence of nucleotides:
*Cytidine Deaminases that convert a C in the RNA to uracil.
*<em />adenosine deaminases that convert an A to inosine,which the ribosome translates as a G.<span>Thus a CAG codon</span><span> (for Gln) can be converted to a CGG codon (for Arg).
<em><u>*Insertion/deletion editing</u></em><em><u /></em><u /> is the insertion or deletion of nucleotides in an RNA.
These alterations are mediated by guide RNA molecules that base-pair as best they can with the RNA to be edited and serve as a template for the addition( or removal) in the target.</span>
This phase is metaphase, and you can remember this by seeing the m means middle.
The chromosomal combination allows for each sex cell that is going to be produced to have different DNA combinations, allowing for the offspring to be not only different from the parents, but also allows for genetic diversity.
Answer:
The shape of an enzyme determines which reaction it can catalyze.
Explanation:
Each enzyme is specific to one type of reaction. According to the structure of each enzyme, it has an active site capable of binding to a specific substrate, so the shape of the enzyme determines the type of reaction to be catalyzed.
Once the reaction occurs, the enzyme releases the product of the reaction and the enzyme is available for another reaction.
Regarding the other options:
- <em>The shape of an enzyme no depends on the reaction that it needs to catalyze.
</em>
- <em>Due to their specificity, enzymes can only catalyze one reaction at a time</em>
- <em>The shape of the enzyme is not altered after the reaction.</em>