Molecular Genetics

1. Molecular Genetics DNA, RNA, and Protein Synthesis

2. DNA • DNA – deoxyribonucleic acid • DNA carries our _______________information. • Recall where is DNA found? ____________ • What is type of macromolecules is DNA an example of? _______________ • Levene – said that ___________ are the subunits of nucleic acids • Two types of nucleic acids - _________ - RNA

3. History • A scientist named _____________ was the first to do an X-Ray model of __________. • Watson and ___________ determined that DNA has a ______________structure. • They were able to determine this with the help of Franklin’s X-Ray Model.

4. DNA DNA is __________ stranded and helical. It is composed of three things: A 5-carbon _________ called deoxyribose, a nitrogenous base, and a ___________________ group. • There are ________ different types of nitrogenous bases - Adenine (A) - Thymine (T) • Cytosine (C) - Guanine (G) • A will bond to T , G will bond with C! A-T , G-C Pyrimidines– Cytosine and Thymine Purines – Adenine and Guanine Purines will always bond to _______________.

5. Chargaff’s Rule – states that the amount of _____ should equal the amount of C and the amount of A should equal the amount of ______. • DNA is like a _______________ where the sides are made up of phosphate and ___________. The rungs of the ladder are made up of ______________. • Phosphate is bonded to Sugar. They make up the “backbone” of DNA. Bonded to the Sugar is the ____________. • The bases are held together by a ________________ bond!

6. Structure DNA RNA

9. How to make a protein • There are three steps involved in making a protein. • 1st– The DNA must be _________________ • 2nd – The DNA must be transcribed. This means the DNA must be made into ____________ • 3rd- The RNA must be translated. This means the RNA must be made into _______________.

10. Central Dogma DNA → RNA → Protein (Transcription) (Translation)

11. DNA Replication • To make a protein, first __________ replication will occur. • It occurs during the _______ phase of the cell cycle. • Where is DNA being replicated in the cell?

12. DNA Replication • First the double stranded DNA will unzip or unwound • DNA helicaseis the ____________ responsible for the unzipping. • Now with a single strand of DNA , DNA polymerase, another enzyme will add the complementary ______________ to the new __________ strand. • After replication, the new DNA strand will be complementary to the old DNA strand.

13. Transcription • After DNA has been replicated, the DNA must be _____________________. • Transcription is _________ being converted into RNA. • DNA codes for many ________________, but DNA can not leave the nucleus. It must be made into __________ to leave the ___________________.

14. RNA • RNA – Ribonucleic Acid • Single ___________________ • Contains a ___________ sugar, a nitrogenous base, and a phosphate group. • G-C and A-U There is no Thymine in RNA, Thymine is replaced with Uracil!!!!! • mRNA, used to ________ the information from the nucleus to the ribosome. * Used in transcription (M-Messenger) • tRNA, used to carry or ____________ amino acids to the ribosome * Used in translation (T-Transfer) • rRNA, used to ________the structures of ribosomes(R-Ribosomal)

15. Transcription • Occurs in the _______________of the cell • RNA polymerase, an enzyme, will unzip the DNA • The new ___________ strand will be complementary to the unzip part of the DNA. • It will follow the base pairing rule! Recall different for RNA! • The ___________ from transcription is ____________ • The mRNA will release and go to the _________________ where ribosomesare located

16. Translation • Translation is converting RNA into protein. • What are the subunits of proteins? _______________ • There are 20amino acids. • Proteins are made on ribosomes; therefore, Translation will occur on a ribsome. • Recall – Where can ribsomes be found in a cell?

17. Codon • Codons are a triplet of bases. mRNA is read in codons. • There are ________codons • Only ______ codons actually code for an __________ acid • There is 1start codon – it also codes for the amino acid _________________ • There are ____stop codons • What is the start codon? ________ • What are the stop codons? _________, UAA, UAG

18. Codon • Three base code – can be in DNA or mRNA

20. Translation • Occurring on the _________________ where mRNA made in transcription will travel outside the _____________ to a ribosome. - During translation, the ___________will come and attach to the codon regions on the mRNA. tRNA has a sequence of bases, called the _____________. tRNA is also carrying the ____________ acid.

21. The anticodon will be complementary to the codon region of mRNA. • Recall again what is the function of tRNA…… • tRNA will _____________the amino acids to the ribosome to begin translation. • So, on one end of the tRNA is the ________________ and the other end has the amino acid attached.

23. Once the tRNAanticodon has attached to the mRNA codon, the appropriate ______________ acid will be released. • Now, the next ____________will be read and the tRNA will release appropriate amino acid. • That amino acid will link with the _______________ amino acids. • Recall- What type of bond holds amino acids together? ____________ • These chains of amino acids will build a ________________ chain which will create a specific protein.