4 nucleotides 2 made of purine bases which are adenine and guanine and 2 pyrimidine bases which are thymine and cytosine.
The four nucleotides in DNA are: adenine, thymine, guanine, and cytosine. Adenine pairs with thymine while guanine pairs with cytosine. There are four nucleotides that make up DNA, each defined by the  nitrogenous bases they contain. They are named adenine, thymine,  guanine how many types of nucleotides are in DNA, and how do they differ. The discovery that DNA was the carrier of genetic information was a process that required many earlier discoveries. The existence of DNA was discovered in the mid 19th century. [ However, it was only in the early 20th century that researchers began suggesting that it might store genetic information. But they all consist of 4 nucleotides 2 made of purine bases which are adenine and guanine and 2 pyrimidine bases which are thymine and cytosine. The purine based nucleotides always pair with their base pair pyrimidine based nucleotide. In DNA Adenine is paired with thymine and guanine pairs with cytosine. There are four nucleotides that make up DNA, each defined by the  nitrogenous bases they contain. They are named adenine, thymine,  guan how many types of nucleotides are in DNA, and how do they differ. The discovery that DNA was the carrier of genetic information was a process that required many earlier discoveries. The existence of DNA was discovered in the mid 19th century.  There are four different DNA nucleotides, each defined by a specific nitrogenous base: adenine (often abbreviated A in science writing), thymine (abbreviated T), guanine (abbreviated G), and cytosine (abbreviated C) (Figure 2).  He called each of these units a nucleotide and suggested the DNA molecule consisted of a string of nucleotide units linked together through the phosphate groups, which are the 'backbone' of the molecule. However Levene thought the chain was short and that the bases repeated in the same fixed order. The discovery that DNA was the carrier of genetic information was a process that required many earlier discoveries. The existence of DNA was discovered in the mid 19th century. [ However, it was only in the early 20th century that researchers began suggesting that it might store genetic information. Nucleic acids, which include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), are made from monomers known as nucleotides. Each nucleotide has three components: a 5-carbon sugar, a phosphate group, and a nitrogenous base. If the sugar is deoxyribose, the polymer is DNA. If the sugar is ribose, the polymer is RNA. When sugar and a nitrogenous base get combined they form a nucleotide. Nucleotides are also known as phosphate nucleotides. Ribonucleotides are nucleotides in which the sugar is ribose. Deoxyribonucleotides are nucleotides in which the sugar is deoxyribose. Nucleic acids are polymeric macromolecules made from nucleotide monomers. In DNA, the purine bases are adenine and guanine, while the pyrimidines are thymine and cytosine. This nucleotide contains the five-carbon sugar deoxyribose, a nitrogenous base called adenine, and one phosphate group. Together, the deoxyribose and adenine make up a nucleoside (specifically, a deoxyribonucleoside) called deoxyadenosine. But they all consist of 4 nucleotides 2 made of purine bases which are adenine and guanine and 2 pyrimidine bases which are thymine and cytosine. The purine based nucleotides always pair with their base pair pyrimidine based nucleotide. In DNA Adenine is paired with thymine and guanine pairs with cytosine. But if it's RNA there is a special exception which replaces thymine with Uracil pairing with aden 1 In DNA, Adenine binds to Thymine. 2  In RNA, Adenine binds to Uracil. 3  These hydrogen-bond interactions between nucleotides C-G and A-T or A-U are referred to as base-pairing or complementary base-pairing. 4  Base-pairing holds the double-stranded DNA molecule together. 1 Nitrogenous bases can form hydrogen bonds. 2  Adenine, Thymine, and Uracil can form TWO hydrogen bonds. 3  Guanine and Cytosine can form THREE hydrogen bonds. 4  In nucleic acids (DNA and RNA), nitrogenous bases can bind to each other by hydrogen bonding.
http://www.answers.com/Q/How_many_types_of_nucleotides_are_present_in_DNA_what_are_they http://www.weegy.com/home.aspx?ConversationId=533FAA55 http://www.answers.com/Q/How_many_types_of_nucleotides_are_present_in_DNA_what_are_they http://www.weegy.com/?ConversationId=533FAA55 http://www.nature.com/scitable/topicpage/DNA-Is-a-Structure-That-Encodes-Biological-6493050 http://www.weegy.com/home.aspx?ConversationId=533FAA55 https://en.wikipedia.org/wiki/Nucleic_acid https://en.wikipedia.org/wiki/Nucleotide http://www.answers.com/Q/How_many_types_of_nucleotides_are_present_in_DNA_how_do_they_differ http://myhome.sunyocc.edu/~weiskirl/nucleotides_nucleicacid.htm
how many types of nucleotides are in dna and how do they differ