Nucleic Acids & Proteins Units 5 & 6

Nucleic Acids Nucleic Acids are Polymers made of Nucleotides 3 Parts: a)Phosphate group b)5-Carbon Sugar c)Nitrogen base 2 Types: DNA & RNA b) 5- Carbon Sugar a) Phosphate Group c) Nitrogen Base

THYMINE URACIL

Nitrogen Bases Pyrimidines = C, T, & U Purines = A & G Pyrimidines ALWAYS bond to Purines G bonds to C A bonds to T or U Single ring Double ring Pyrimidines Purines

RNA Sugar = Ribose RNA is Single Stranded RNA has Uracil Sugar & phosphate backbone Nitrogen Bases

DNA Sugar = Deoxyribose DNA is Double Stranded DNA has Thymine Sugar & phosphate backbone Nitrogen Bases Hydrogen Bonds

A bonds to T; G bonds to C Hydrogen bonds hold Nitrogen bases together to form the Double helix DNA

DNA is found in the Nucleus of eukaryotic cells in the form of Chromosomes

Sections of DNA that code for a protein are called Genes Chromosomes are made of DNA wound around proteins called Histones Homologous chromosomes have the same Genes (possibly different alleles)

DNA Replication Original strands are used as a Pattern/Template to build new Complimentary DNA strands Enzymes help with this process: Helicase breaks the hydrogen bonds between the complimentary strands DNA Polymerases build the new strands and then proofread the nucleotide sequence

2 Identical DNA molecules are produced. Each molecule is made of one ORIGINAL strand and one NEW strand. Semi-conservative DNA Replication

ENZYMES of DNA Replication UNZIPS STRANDS ADDS NEW NUCLEOTIDES

Leading strand (3’ end) Lagging strand (5’ end)

DNA polymerase can only move towards the 5’ end of the original DNA molecule (New DNA is built 5’ to 3’) This means the Lagging strand is built in small sections called Okazaki fragments.

Central Dogma DNA  RNA  Protein

Protein Synthesis Transcription Translation

Protein Functions: Transport of substances, Enzymes that control the rate of reactions, provide Support, build Tissues, & fight Infections 3 Central Carbon 4 Amino Group 5 Hydrogen 6 Carboxyl Group 7 R Group Proteins are Polymers made of Amino Acids 4 Parts: Central Carbon Amino group Hydrogen Carboxyl group & R group

3 Types of RNA mRNA = Copy of gene/DNA (instructions for making the protein) tRNA = Translates/Decodes mRNA and Transfers/Delivers amino acids to the ribosome in the correct sequence rRNA = Ribosomes are made of rRNA which Bond amino acids together to build the Polypeptide (protein) a) Messenger RNA b) Ribosomal RNA c) Transfer RNA

Transcription the process of Copying DNA into the complimentary sequence of mRNA The enzyme that copies the DNA (gene) into mRNA is RNA polymerase No T in RNA so A bonds to U

RNA Polymerase Works just like DNA polymerase EXCEPT it adds RNA nucleotides

Transcription occurs in the Nucleus

Translation Begins when the mRNA leaves the nucleus and goes to the Ribosome tRNA decodes the mRNA 3 bases at a time Codon = 3 base sequence on mRNA Codons are complimentary to the Anticodons on the tRNA rRNA forms Peptide bonds between Amino Acids to form the Polypeptide (protein)

Translation Anticodon Amino Acid Codon

Transcribe the following DNA into mRNA DNA: TAC – CCG – GAT – TAG – ATC mRNA: ____ - ____ - ____ - ____ - ___ Translate the above mRNA into the correct sequence of Amino Acids using the Codon Chart Protein: ____ - ____ - ____ - ____ - ____ AUGGGC CUA AUCUAG Met GlyLeu Ile STOP

1 DNA = Template 2 mRNA built by RNA polymerase 3 Codons on mRNA 4 mRNA goes to ribosome 5 tRNA carries amino acids 6 tRNA Anticodon decodes mRNA codons 7 Amino acid bonded to Polypeptide 8 tRNA goes to pick up another Amino Acid