Hello guys, I just wanted some clarification of these question.

Question

1. A sequence of amino acids in a certain protein is found to be -Ser-Pro-Gly-Gly-. The sequence is most probably part of a
1. a-helix
2.b-turn (b-bend)
3. parallel b-pleated sheet
4. a-sheet.

2. The pathological changes in sickle cell anemia are due to
a. loss of ability of the heme group to bind oxygen
b. decrease in the solubility of deoxyhemoglobin
c. increase in the solubility of oxyhemoglobin
d. dissociation of iron(II)ion from heme.