[mÌ¥ÉÌÅ]) are an ethnic group from the mountainous regions of China, Vietnam, Laos, and Thailand. Hmong are also one of the sub-groups of the Miao ethnicity (èæ) in southern China. Hmong groups began a gradual southward migration in the 18th century due to political unrest and to find more arable land.
In this way a DNA molecule is similar in structure to a ladder in which the sugar and phosphate groups make the uprights and the nitrogen base groups the rungs. There are four types of nitrogen bases or base groups. 1  Adenine (A). 2  Thyamine (T).3  Cytosine (C). 4  Guanine (G).he nucleotides in the DNA molecule are linked in series from one phosphate, to the next sugar, to the next phosphate and so on. The DNA molecule can be considered as a ladder with the phosphate and the sugar molecules making up the uprights and the bases making up the rungs.
The phosphate group of one nucleotide links to the deoxyribose unit of another to form the backbone of the DNA strand. The nucleobases form the ladder rungs when the two strands align and twist to form the classical double-helix structure.ucleotides that form the strands of the DNA structure are complex molecules which consist of both a phosphate moiety and a nucleobase (adenine, guanine, cytosine or thymine) joined to a five-carbon sugar (deoxyribose).