Question

Which of these are the repeating units that form a DNA molecule?


A fatty acids
B nucleotides
C amino acids
D chromosomes

Answer 1

B

Answer 2

Starch turns blue-black in the presence of iodine solution. A selectively permeable dialysis sac containing a starch solution is placed into a beaker of iodine solution.


If the dialysis sac is permeable only to water and iodine, what will the solutions in the beaker and the sac look like after two hours?


A The iodine solution in the beaker will turn blue-black; the starch solution will not change.
B The starch solution in the dialysis sac will turn blue-black; the iodine solution will not change.
C Neither solution will turn blue-black.
D Both solutions will turn blue-black.