1.Picture a ladder, twisted from top to bottom,this is like a strand of DNA looks like. The structure is called a double helix. DNA is essentially made of sugar, phosphate and bases, bonded together by hydrogen. Most of the life forms on earth carry these strands of DNA within their cells. The twisted sides of the ladder are made of a particular kind of sugar called deoxyribose, in combination with a phosphate. The supportive of the ladder are made of four different base molecules, called adenine, guanine, cytosine and thymine, abbreviated A, G, C and T. A and G are larger, double-ringed in molecular structure, and are called purines. C and T are smaller, single-ringed, and are called pyrimidines. A always pairs up with T, and G always pairs with C. There are two hydrogen bonds in the A-T base pair, and three hydrogen bonds in the G-C base pair. DNA stores the genetic code, or blueprint, for the life form and replicates the code to the cells of the body. Most life forms, including animals, plants and humans, had DNA, except for some viruses, which only have RNA. RNA is a single strand of phosphate and ribose -- another type of sugar. RNA is responsible for reproducing proteins. 2. Chargaff\'s rules states that DNA from any cell of all organisms should have a 1:1 ratio(base Pair Rule) of pyrimidine and purine bases . More specifically, that the amount ofguanine is equal to cytosine and the amount of adenine is equal to thymine. Solution 1.Picture a ladder, twisted from top to bottom,this is like a strand of DNA looks like. The structure is called a double helix. DNA is essentially made of sugar, phosphate and bases, bonded together by hydrogen. Most of the life forms on earth carry these strands of DNA within their cells. The twisted sides of the ladder are made of a particular kind of sugar called deoxyribose, in combination with a phosphate. The supportive of the ladder are made of four different base molecules, called adenine, guanine, cytosine and thymine, abbreviated A, G, C and T. A and G are larger, double-ringed in molecular structure, and are called purines. C and T are smaller, single-ringed, and are called pyrimidines. A always pairs up with T, and G always pairs with C. There are two hydrogen bonds in the A-T base pair, and three hydrogen bonds in the G-C base pair. DNA stores the genetic code, or blueprint, for the life form and replicates the code to the cells of the body. Most life forms, including animals, plants and humans, had DNA, except for some viruses, which only have RNA. RNA is a single strand of phosphate and ribose -- another type of sugar. RNA is responsible for reproducing proteins. 2. Chargaff\'s rules states that DNA from any cell of all organisms should have a 1:1 ratio(base Pair Rule) of pyrimidine and purine bases . More specifically, that the amount ofguanine is equal to cytosine and the amount of adenine is equal to thymine..