How does DNA/RNA polymerase always have the correct free nucleotide next to it as it rapidly synthesizes?

Question

I understand how DNA and RNA polymerase work and I also know they move at amazing rates. as the polymerase moves across the template strand it has to "capture" free nucleotides? is there just a high concentration of nucleotides around the enzymes at all times?

Answer 1

Nucleotides in the form of ATP (Adenine triphosphate not adenosine), GTP, CTP, and TTP are availible in concentration all around the cytosol. The polymerase easily grabs these.

Answer 2

Yes, there is just a high concentrations of nucleotides throughout the cell at all times (unless the cell is energy-starved).

Answer 3

There are only four different nucleotides. It would be easy to grab the right one.