Questions: Circle all that apply. Which of the following are properties of DNA? a. Double helix. b. Confined to the nucleus. c. Contains the sugar ribose. d. Contains the base thymine (T). e. Single stranded. f. Can move between the nucleus and the cytosol. g. Contains the base uracil (U). h. Contains the sugar deoxyribose.

The correct answers are:
a. Double helix.
d. Contains the base thymine ( $T$ ).
h. Contains the sugar deoxyribose.

Explanation for each option:
a. Double helix: Correct. DNA is structured as a double helix, consisting of two strands that wind around each other.
b. Confined to the nucleus: Incorrect. While DNA is primarily located in the nucleus in eukaryotic cells, it is not exclusively confined there, as mitochondrial DNA exists outside the nucleus.
c. Contains the sugar ribose: Incorrect. DNA contains the sugar deoxyribose, not ribose. Ribose is found in RNA.
d. Contains the base thymine ( $T$ ): Correct. DNA contains the base thymine, which pairs with adenine.
e. Single stranded: Incorrect. DNA is typically double-stranded, forming a double helix.
f. Can move between the nucleus and the cytosol: Incorrect. DNA itself does not move between the nucleus and the cytosol; however, RNA transcribed from DNA can move to the cytosol.
g. Contains the base uracil (U): Incorrect. DNA contains thymine instead of uracil, which is found in RNA.
h. Contains the sugar deoxyribose: Correct. DNA contains deoxyribose, which is part of its backbone structure.

In summary, the properties of DNA include being a double helix, containing the base thymine, and containing the sugar deoxyribose.