Question

How many different nucleotides can be formed?​

Answer 1

Respuesta:

there are four different types of DNA nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C).

Explicación:

Understand DNA replication

One schematic shows a region of DNA, with a portion of single-stranded DNA and most of the double-stranded DNA. The sugar-phosphate backbone is represented as a segmented gray cylinder. Nitrogen bases are represented by blue, orange, red, or green vertical rectangles attached on each segment of the sugar-phosphate backbone. A transparent blue globular structure, representing the enzyme DNA polymerase, is attached to a multi-nucleotide region along the DNA strand about a quarter of the way from the right side. DNA is single-stranded to the right of DNA polymerase and double-stranded to the left, indicating that DNA polymerase moves from left to right as the DNA strand replicates. The region of DNA bound by DNA polymerase is visible within the transparent enzyme at higher magnification.

Figure 1: DNA polymerase assembles nucleotides to form a new DNA strand.

To understand how Sanger sequencing works, it is first necessary to understand the DNA replication process as it exists in nature. DNA is a double-stranded helical molecule made up of nucleotides, each of which contains a phosphate group, a sugar molecule, and a nitrogen base. Because there are four natural nitrogenous bases, there are four different types of DNA nucleotides: adenine (A), thymine (T), guanine (G), and cytosine (C). Within double-stranded DNA, nitrogenous bases on one strand pair with complementary bases along the other strand; in particular, A always pairs with T and C always pairs with G. Then, during DNA replication, the two strands of the double helix separate. This allows an enzyme called DNA polymerase to access each strand individually (Figure 1). As DNA polymerase travels down single-stranded DNA, it uses the nucleotide sequence of that strand as a template for replication. Thus, whenever the DNA polymerase recognizes a T in the template strand, it adds an A to the complementary daughter strand that it is forming; similarly, whenever it finds a C in the original strand, it adds a G to the child strand. This process occurs along both strands simultaneously, resulting in the eventual production of two double helix molecules, each of which contains an "old" and a "new" strand of DNA. Whenever it finds a C in the original thread, it adds a G to the child thread. This process occurs along both strands simultaneously, resulting in the eventual production of two double helix molecules, each of which contains an "old" and a "new" strand of DNA. Whenever it finds a C in the original thread, it adds a G to the child thread. This process occurs along both strands simultaneously, resulting in the eventual production of two double helix molecules, each of which contains an "old" and a "new" strand of DNA.