Osphena Â® should not be used if you have unusual vaginal bleeding, have or have had certain types of cancers (including cancer of the breast or uterus), have or have had blood clots, have had a stroke or heart attack, have severe liver problems, are allergic to Osphena Â® or any of its ingredients, or think you may be pregnant.
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 DNA nucleotide is composed of 3 main units: a sugar, a phosphate group, and a nitrogenous base. While the sugar and phosphate group alternate in sequence and form the backbone of the DNA double helix, the nitrogenous bases may differ in every adjoining nucleotide.The four nitrogenous bases present in DNA are adenine (A), guanine (G), cytosine (C) and thymine (T).In RNA, the only differing nitrogenous base is uracil (U) (which replaces thymine in DNA and differs thymine only by the missing methyl group at carbon 5 of the pyrimidine ring).hile the sugar and phosphate group alternate in sequence and form the backbone of the DNA double helix, the nitrogenous bases may differ in every adjoining nucleotide. The four nitrogenous bases present in DNA are adenine (A), guanine (G), cytosine (C) and thymine (T).