1: The process of osmosis would cause water to move into the cells causing them to swell and possibly burst. Many freshwater one celled organisms have structures called contractile vacuoles. These structures collect and pump out excess water that accumulates in the cell.
2: During active transport, a protein pump uses energy, in the form of ATP, to move molecules from an area of low concentration to an area of high concentration. An example of active transport is the sodium-potassium pump, which moves sodium ions to the outside of the cell and potassium ions to the inside of the cell.
The single-nucleotide polymorphism in human genomes is a substitution of a single nucleotide which occur in a specific position at the genome. The A-T nucleotide may appear dominant in the most population, while the remaining minor population may have the G-C nucleotide. The DNA molecule in the population at this site have A-T or G-C.