Internal control: This is a control sequence that is amplified in the same reaction as the target sequence and detected with a different probe (i.e., duplex PCR is carried out). An internal control is often used to rule out failure of amplification in cases where the target sequence is not detected.
How it works. A symporter is an integral membrane protein that is involved in the transport of many differing types of molecules across the cell membrane. The symporter works in the plasma membrane and molecules are transported across the cell membrane at the same time, and is, therefore, a type of cotransporter. The transporter is called a symporter, because the molecules will travel in the same direction in relation to each other. This is in contrast to the antiport transporter. Typically, the ion will move
The free energy stored in this gradient is used by Na + -coupled transporters to drive the uphill movement of substrates. Two types of secondary active transport: Cotransport and Exchange. Two variations of secondary active transport exist: cotransport (also known as symport) and exchange (also known as antiport).