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Deoxyribose shows as 5-membered rings - 4 greys [carbon] and 1 oxygen [red], with another projecting carbon connecting to phosphate, which is orange with projecting oxygens [red]. Across the middle of the molecule are the bases adenine and thymine, showing the nitrogen atoms in blue. In each case the bases do not directly contact their partner on the opposite strand, to which they are held by 2 hydrogen bonds. |
This represents a pair of nucleotides, basic subunits (monomers) which can be built up to make up the DNA molecule (a biological polymer). The molecules shown here are basically one rung of the DNA ladder.
Each nucleotide consists of a 5-carbon sugar deoxyribose unit attached to a phosphate unit at one side and one of four nitrogen-containing bases on the other side. In this view two nucleotides, adenosine phosphate and thymidine phosphate, are shown. Click below for different display options - hovering with the mouse shows information
Adenosine phosphate is adenine + deoxyribose + phosphate. Thymidine phosphate is thymine + deoxyribose + phosphate. Each nucleotide appears to be upside down compared with its partner, and so are the deoxyribose and phosphate units. This is because the 2 DNA strands are built up from alternating sugar-phosphate strands pointing in opposite directions. |
