DNA and RNA DNA and RNA

DNA DNA -Deoxyribonucleic acid DNA -Deoxyribonucleic acid The nucleic acid that stores and transmits the genetic information from one generation of an organism to the next. The nucleic acid that stores and transmits the genetic information from one generation of an organism to the next. made of a sugar molecule called deoxyribose and a phosphate group attached to a nitrogen base. Called nucleotides made of a sugar molecule called deoxyribose and a phosphate group attached to a nitrogen base. Called nucleotides

DNA Structure 4 nitrogenous bases 4 nitrogenous bases Adenine - A Adenine - A Thymine - T Thymine - T Cytosine - C Cytosine - C Guanine - G Guanine - G Base pairing Base pairing occurs when bonds are formed between bases occurs when bonds are formed between bases ONLY A-T and C-G ONLY A-T and C-G

DNA Hershey and Chase Hershey and Chase Concluded that genetic information was DNA not Protein Concluded that genetic information was DNA not Protein Watson and Crick Watson and Crick Discovered the structure of DNA Discovered the structure of DNA to be a double helix, in which two strands were wound around each other.

DNA Structure

Chromosomes and DNA Replication DNA replication- DNA replication- Before a cell divides the DNA is duplicated by opening the double helix and completing base pairing to make more DNA. Before a cell divides the DNA is duplicated by opening the double helix and completing base pairing to make more DNA. **. If an original strand is ATTCGA then its new strand will be TAAGCT

DNA Replication

Complete the new strand of DNA Complete the new strand of DNA A T G C T G A C C C T T G DNA Replication TCACGAACGGTAG

RNA How is RNA different from DNA How is RNA different from DNA Single-stranded Single-stranded Sugars Sugars Ribose instead of Deoxyribose Ribose instead of Deoxyribose Nitrogenous Bases Nitrogenous Bases Uracil takes the Uracil takes the place of Thymine

Three types of RNA mRNA-messanger mRNA-messanger Carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell. Carries copies of instructions for the assembly of amino acids into proteins from DNA to the rest of the cell. rRNA rRNA Makes up the major part of ribosomes Makes up the major part of ribosomes tRNA tRNA Transfers amino acids to ribosome's during protein synthesis Transfers amino acids to ribosome's during protein synthesis

Central Dogma of Biology All living things have the same way of reading and expressing genes: All living things have the same way of reading and expressing genes: DNA  RNA  proteins DNA  RNA  proteins

Transcription Transcription Transcription Process of copying DNA to RNA Process of copying DNA to RNA 1. DNA acts as template 2. RNA Polymerase (Enzyme) starts at beginning 3. Base Pairing A-UC-G 4. Single strand

Transcription Complete a strand of RNA using this DNA template Complete a strand of RNA using this DNA template A T G C T T G A C A C T T G UCACGAAACUGUAG

Translation During translation, the cell uses information from the messenger RNA to produce proteins. Codon –Three consecutive nucleotides that specify a single amino acid UCACGAAACGGUAG

Translation Decoding mRNA into amino acids so they can make protein Decoding mRNA into amino acids so they can make protein Genetic Code Chart is used for Amino acids Genetic Code Chart is used for Amino acids

Translation Lets try it….. Lets try it….. AUG UUC GGC GUU CCA CAG UAG AAU STARTPHENYL- ALANINE GLYCINEVALINEPROLINEGLUTAMIMNESTOP

MUTATIONS Two types of Mutations Two types of Mutations Gene Gene A change in the nucleotide sequence can result in a mutation. A change in the nucleotide sequence can result in a mutation. Caused by Caused by Insertion -adding a nucleotide Insertion -adding a nucleotide Deletion –deleting a nucleotide Deletion –deleting a nucleotide Substitution –change a nucleotide Substitution –change a nucleotide … Examples Sickle Cell, cancer, etc

Mutations Chromosomal Mutation Chromosomal Mutation A change in the number or structure of the chromosome. A change in the number or structure of the chromosome. Caused by Caused by Deletion-Part is dropped Duplication-Too much is copied

Mutations Inversion Switch the order Inversion Switch the order Translocation-move from one place to another Translocation-move from one place to another Chromosomal Mutation Chromosomal Mutation

Consequences of mutations In somatic (body) cells are not passed onto the offspring. In somatic (body) cells are not passed onto the offspring. Can be occur randomly or be caused by exposure to high-energy radiation and toxic chemicals Can be occur randomly or be caused by exposure to high-energy radiation and toxic chemicals One way people develop cancer-especially skin cancer One way people develop cancer-especially skin cancer In gametes condition is passed to offspring may or may not be a problem In gametes condition is passed to offspring may or may not be a problem