The right answer is a person has more than two alleles for a certain trait.
Duplication is a genetic mutation characterized by the doubling of genetic material on a chromosome. There are several mechanisms that result in the duplication of either a large chromosomal portion, a gene, or a nucleotide sequence.
When the cardiac muscle cell is at rest, the concentration of sodium and calcium is greater on the outside of the cell.
The resting membrane potential (the cardiac muscle cell is at rest) is characterized by more negatively charged inside of the membrane comparing to the outside. The main ions found outside the cell at rest are: sodium (Na+), and chloride (Cl−), and Ca2+ whereas inside the cell it is mainly potassium (K+).
D.mutualism,both parties benefit