Answer: The broadest group for classification is "Domain".
Domain is a taxonomic group that lies above kingdom level and divides all life forms into three broad categories that is Archea, Bacteria, and Eukarya.
On the contrary, Taxon is a rang or a unit (like species, genus, class) that is designated in the biological classification of organisms.
Thus, b) Domain is the right answer.
Chewing a saltine cracker is a physical change
In general, a point mutation alters a single base in the DNA (gene) which can potentially alter the identity of a SINGLE amino acid in the protein sequence.
<span>Also, it might be a good idea to ask biology questions in the Science and Math section. More of us answer there more often than here.</span>
I think your answer is: Proteins
Hope this helps!
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