Question

Do you think Tm is a constant, or can it depend on other small molecules in the solution? Do you think high salt concentrations increase, decrease, or have no effect on Tm?

Answer 1

Tm, or melting temperature, can depend on other small molecules in the solution. High salt concentrations can decrease the Tm.

Step-by-step explanation:

Tm, also known as melting temperature, can depend on other small molecules in the solution. The presence of certain molecules can affect the stability of the DNA double helix and, therefore, the Tm. For example, high salt concentrations can decrease the Tm. This is because the salt ions compete with the DNA strands for bonding with water molecules, which weakens the hydrogen bonds holding the DNA strands together. As a result, the DNA strands separate at a lower temperature, decreasing the Tm.