DNApart 3

Prep by :Mohamed Abdukadir KalifMphil in optometry

As we told on our previous lectures a nucleotide looks like the one in

the picture , and many such nucleotides put together will make

DNA

• Every nucleotide has two ends , one end is carbon position number 5 in which now there is phosphate attached , and the other end is carbon position number 3

• In DNA the nucleotide it contains are connected in such a way , that the carbon position number 3 end of Adenine is connected with carbon position number 5 of Guanine , and u can see in the upcoming picture

So what happens When nucleotides wants to attach with

one another to make DNA

When in the cell DNA synthesis is going on , the nucleotide which are present with in the cell should be triphosphate , because

the triphosphate are rich of energy they will be accepted in other nucleotides in

order to make a chain of DNA

When a nucleotide of a triphosphate comes to attach with another nucleotide , energy should

be released in order to create a strong bond between the two nucleotides ,

to make a chain of DNA

In DNA formation the nucleotides are held together by strong bonds

which are created by the release of energy , these bonds are called

phosphodiester bond

The enzyme which can break down the phosphodiester bond is called

Nucleases

• And the enzyme which can break down the DNA is called DNAases

• And the enzyme which can break down the RNA is called RNAases

• To be continued