dna transcription and the translation.pptx

in this slide we explain you the concept of transcription of dna along with the translation of the dna in easy way.

1. What is DNA? Replication and Transcription By Abhay, Akarsh Nitin, osho Adarsh, Abudullah

2. DNA Structure DNA Stands for Deoxyribonucleic acid . DNA is a macromolecule. It is a type of nucleic acid . DNA is a polymer (many units connected to each other) of nucleotides.

3. People important to the discovery of DNA Structure Watson, Crick, & Wilkins were awarded a Nobel Prize because they were the first to make a model of the double helix shape Chargaff did experiments to come up with the base pairing rules (A-T, C-G). Franklin took x-ray pictures of DNA, first to show the shape was a double helix, called image 51

4. What is the monomer of DNA? DNA is a large molecule made of small parts called nucleotides. Each nucleotide contains three parts: 1. sugar (deoxyribose) 2. phosphate group 3. nitrogen base (any of 4, adenine, thymine, cytosine or guanine)

5. Complementary Base Pairing DNA has two sides or strands. We say that one strand is complementary to the other, meaning that they use Chargaff’s base pairing rule to match up. Chargaff’s rule states that: adenine always pairs with thymine (A-T) & cytosine always pairs with guanine (C-G) The two strands of DNA are held together by hydrogen bonds .

6. DNA Replication DNA replication is the process where a molecule of DNA makes an exact copy of itself. (see foldable model) DNA "unzips", which means it breaks hydrogen bonds and opens up. New nucleotides come in and bond to the open strands using the base pairing rules.

7. Semi-Conservative Replication Each new molecule that results is half "new" and half "old" - this helps minimize mistakes in copying - we call this semi-conservative replication

8. DNA Replication Steps of DNA Replication: The parental DNA molecule unwinds and unzips. Both parental strands serve as templates for new strands. Free nucleotides link to complementary bases on each strand. Two identical DNA molecules result, each composed of one parental strand, and one new strand.

9. Enzymes in DNA replication Helicase unwinds parental double helix Binding proteins stabilize separate strands DNA polymerase III binds nucleotides to form new strands Ligase joins Okazaki fragments and seals other nicks in sugar-phosphate backbone Primase adds short primer to template strand DNA polymerase I (Exonuclease) removes RNA primer and inserts the correct bases

10. Initiation: RNA polymerase, the main transcription enzyme, binds to a promoter sequence near the beginning of a gene. This binding forms a transcription bubble , where the DNA double helix unwinds. One of the exposed DNA strands serves as the template strand for RNA synthesis. Elongation: RNA polymerase moves along the template strand, adding complementary RNA nucleotides. The RNA product is synthesized in the 5’ to 3’ direction . As RNA polymerase advances, the DNA helix re-forms behind it. Termination: Transcription ends when specific sequences in the RNA signal that the transcript is complete. These termination signals prompt RNA polymerase to release the newly formed RNA molecule. The RNA product is now ready for further processing or translation into proteins. Initiation : RNA polymerase, the main transcription enzyme, binds to a promoter sequence near the beginning of a gene. This binding forms a transcription bubble, where the DNA double helix unwinds. One of the exposed DNA strands serves as the template strand for RNA synthesis. Elongation : RNA polymerase moves along the template strand, adding complementary RNA nucleotides. The RNA product is synthesized in the 5’ to 3’ direction. As RNA polymerase advances, the DNA helix re-forms behind it. Termination : Transcription ends when specific sequences in the RNA signal that the transcript is complete. These termination signals prompt RNA polymerase to release the newly formed RNA molecule. The RNA product is now ready for further processing or translation into proteins