DNA and Replication, RNA and Transcription, Translation (= Transcription and Translation = processes in protein synthesis)

Videos Crash Course DNA Bozeman Biology DNA

DNA 1.Deoxyribonucleic Acid 2.Prokaryotic = cytoplasm Eukaryotic = Nucleus (unable to leave) 3. Chromatin, chromosomes, genes

DNA 4. The main role of DNA molecules is information storage. DNA = instructions needed to construct components of cells, such as proteins and RNA molecules.

DNA Structure 5.Two sided molecule * Steps in middle * Resembles a twisted ladder

6.Referred to as the DOUBLE HELIX Subunits = NUCLEOTIDES = 8. = **See diagram on board** 7. DNA building block consisting of a 5-carbon deoxyribose sugar, a phosphate group, and one of 4 nitrogen bases.

DNA Structure 9.These are the names of the various nitrogen bases (go across the middle to connect the two sides). A = AdenineC = Cytosine G = GuanineT = Thymine 10. Nitrogen bases that make up the “rungs” of the DNA ladder

11.On the DNA Molecule: Adenine always bonds with Thymine A – T or T – A Cytosine always bonds with Guanine C – G or G – C (These are called complimentary nitrogen base pairs. They are held together by a weak hydrogen bond)

12. The sides of the DNA are made of alternating Phosphate and Deoxyribose sugar molecules.

13. In 1953 James D. Watson and Francis Crick suggested what is now accepted as the first correct double-helix model of DNA structure in the journal Nature. Their double-helix, molecular model of DNA was then based on a single X-ray diffraction image taken by Rosalind Franklin and Raymond Gosling in May 1952, as well as the information that the DNA bases were paired—also obtained through private communications from Erwin Chargaff in the previous years.

Watson and Crick Watson and Crick along with Maurice Wilkins were awarded the (14.) Nobel Prize in 1962 for their discovery. Wilkins’ partner, Rosalind Franklin died before the award was presented.

15. A section of DNA. 16. Genes provide the cell with the specific information (“recipe”) needed to produce a specific protein. 1 gene = 1 protein

DNA Replication 1. The process performed by cells to create two exact copies of the DNA. 2.Occurs in the NUCLEUS of eukaryotic cells. 3. Takes place at the during the Synthesis stage of interphase just prior to mitosis or meiosis.

1. DNA helicase separates the 2 sides of DNA at the replication fork.

2. DNA polymerase connects free nucleotides to the nitrogen bases on the original sides of the DNA that are serving as templates

3. Two new molecules of DNA are created, each consisting of a side of the original DNA and a newly formed side.

DNA Replication Craig Savage DNA Replication

Step 1Step 2 Step 3

Step 1 Step 2 Step 3 Step 1 = Unzipping = The DNA unwinds and hydrogen bonds between the complimentary bases are broken. The two sides separate.

Step 1 Step 2 Step 3 Step 2 =Free DNA nucleotides move in between the sides and begin to bond complimentary bases with existing bases on each side.

Step 1 Step 2 Step 3 Step 3 =Two identical semi- conservative DNA molecules are created = each has one side from the original strand of DNA and a newly formed side.

DNA Replication DNA Replication Animation ComplexReplication DNA Replication Bozeman BioReplication

RNA 1.Ribonucleic Acid 2.In the cytoplasm of prokaryotic cells; in the nucleus and the cytoplasm of eukaryotic cells. 3.Functions to carry genetic information to the ribosomes (=mRNA) and to transfer amino acids to the ribosomes (=tRNA).

RNA Structure Bozeman Bio RNA 4.Subunits = NUCLEOTIDES RNA building block consisting of a 5- carbon ribose sugar, a phosphate group, and one of 4 nitrogen bases Nitrogen bases = A = Adenine C = Cytosine G = Guanine U = Uracil

RNA Functions 6.mRNA = messenger RNA 7.Carries genetic information (=a copy of 1 DNA gene) to the ribosomes. 8.A single sided molecule composed of nucleotides. *not a double helix *shorter than DNA (only the length of 1 gene)

mRNA Structure

RNA 9.The copying of a DNA gene to create a complimentary strand of mRNA. The result of this process is mRNA. 10. In the nucleus of eukaryotic cells.

The Process of TRANSCRIPTION

1.The DNA unwinds at the gene to be transcribed. 2.Unzipping = H bonds break between the bases on the DNA. 3.The sides of the DNA separate.

4.Free RNA nucleotides move in between the DNA strands. *RNA nucleotides temporarily bond with their complimentary bases on the one side of DNA. REMEMBER: NO “ T ” base ON RNA!

5. A complimentary mRNA is created by copying the DNA gene. * The newly created mRNA exits the DNA and the nucleus. * mRNA travels to a ribosome to be “read” During the process of translation.

Transcription Animation Transcription #1 Transcription #2

Found in the nucleus Nucleotides present N bases = A,T,G,C Double helix Ribose sugar N bases = A,U,G,C Complimentary bases held together with an H bond Deoxyribose sugar Single strand Contains many genes

Travels to a ribosome Produced during replication Ester bonds present Produced during transcription

TRANSLATION 11.The reading of the mRNA by a ribosome to assemble an amino acid chain and create a protein. 12. Ribosomes 13. mRNA carries information from a DNA gene to a ribosome.

TRANSLATION 14.A triplet of letters on mRNA *Most codons code for specific amino acids. *See mRNA Codon Chart**

mRNA Codons for Amino Acids START Codon STOP codons

15.tRNA carries amino acids from the cytoplasm to the ribosome during translation of mRNA. 16.Anticodon = the three tRNA bases complimentary to those in a mRNA codon. 17.Protein subunits = amino acids.

Translation = diagram on board; notes below: 1.mRNA attaches to a ribosome 2.If “start” codon (= AUG) is read, the ribosome begins to read the mRNA 1 codon at a time. 3.tRNA’s deliver amino acids to the ribosome – peptide bonds links amino acids together. 4.Polypeptide chain of amino acids is released when a “stop” codon is read. 5.Polypepide chain folds into its 3-D shape = protein

Translation Animations #1 #2 DNA Processes Animation (for Worksheet)DNA Processes Animation Transcription and Translation Bozeman Protein Synthesis Crash Course