Question

Two complementary strands of DNA can exist in solution in the form of a duplex (double-stranded form) or can exist as separate strands ("random coils"), depending on the position of the equilibrium shown below. Double-stranded form < = = > single strands ("random coil") With regard to Enthalpy and Entropy, match the interactions that favor the form of DNA listed.

What is the enthalpic term favoring single stranded DNA?

A. Hydrogen Bonding

B. Conformational

C. Base Stacking

D. van der Waals

E. Electrostatic

F. Cannot favor single stranded DNA

What is the entropic term favoring single stranded DNA?

Electrostatic, Hydrogen Bonding, conformational, Base Stacking, van der Waals, or Cannot favor single stranded DNA

What is the enthalpic term favoring double stranded DNA?

Hydrophobic Effect, Hydrogen Bonding, van der Waals, Electrostatic, Conformational, Cannot Favor double stranded DNA

What is the entropic term favoring double stranded DNA?

Electrostatic, Hydrogen bonding, Conformational, Base Stacking, van der Waals, or Cannot favor single/double stranded DNA

Answer 1

1) Entahlpic term f) cannot favour single stranded DNA

2) Entropic term favoring single stranded DNA is the Base stacking interaction.  

As, Single-stranded DNA does not have the base pairing interaction found in dsDNA. However, some ssDNA shows base stacking interaction, which can significantly affect its elasticity and conformation.

3) The enthalpic term involved in double stranded DNA is hydrogen bonding, hydrophobic effect, van der waal force

4) The entropic term that is involved in dsDNA is Conformational and Base stackinh