Triops is a genus of small crustaceans in the order Notostraca (tadpole shrimp). Some species are considered living fossils, with a fossil record that reaches back to the late Carboniferous, 300 million years ago.
DNA structure. DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).The order of these bases is what determines DNA's instructions, or genetic code.NA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).
A molecule of DNA is double-stranded. The molecule has the shape of a double helix, typically right handed (B form DNA). The DNA molecule consists of two complementary strands oriented in an antiparallel fashion.Each strand is composed of nucleotides.A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.he twisted ladder metaphorA DNA molecule is often likened to a spiral (or twisted) ladder. In this analogy, the rungs of the ladder are the base pairs (A-T and G-C). The sides of the ladder are the sugar-phosphate backbones of the two strands.