Why is a DNA molecule called a double helix?
A. A DNA molecule always has two strands of nucleotides.
B. Each nucleotide has two main parts: a base and a phosphate.
C. The sugar and phosphate parts are the same in all DNA molecules.
D. There are two kinds of nitrogen bases in a DNA molecule.

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

Which represents the cross between parent plants if one is heterozygous for yellow-colored pods and the other is homozygous for green-colored pods? yy  ´    ´    ´    ´  yy

(select all the correct choose each statement that is scientific. - the opinions of randomly selected participants in a survey prove the idea that global temperatures are not increasing on earth. - the universe's average temperature and rate of expansion support the idea that it began as one super-dense and hot mass 13.8 billion years ago. - ocean tides are caused by the uneven gravitational pulls of the moon and sun on different parts of earth. - human life is more valuable than other forms of life on earth because humans are more intelligent than other organisms.