Write the COMPLEMENTARY DNA strand for each sequence. 1. TACGGCAAACTTACT 2. TACGCCATT 3. TACAAAAAGTGGATC DNA Replication Review • Flash Tutorial Learning Targets “I Can. . .” -List three ways that RNA is different from DNA. -List the three types of RNA. -Describe the role of mRNA and tRNA during protein synthesis. -Define “transcription” and where it occurs in the eukaryotic cell. -Define “translation” and where it occurs in the eukaryotic cell. Protein Synthesis DNA RNA Protein What is RNA? Ribonucleic Acid 1. Nucleotides A G C U ADENINE GUANINE CYTOSINE URACIL What is RNA? Ribonucleic Acid 2. Contains the sugar ribose, rather than deoxyribose 3. Is single stranded, rather than double stranded 4. Three types: a. mRNA (Messenger) b. tRNA (Transfer) c. rRNA (Ribosomal) Why do we have protein in our bodies? 1. 2. 3. 4. Enzymes Major component of the cell membrane Structural component of skin and muscle Basically, DNA codes for protein, which become you! Recall: DNA is made of nucleotides strung together into a chain. These nucleotides code for amino acids. 1. Amino acids: the subunits strung together in a protein chain 2. The four nucleotides are grouped into threes: these groups of three are called codons. Recall: DNA is made of nucleotides strung together into a chain. These nucleotides code for amino acids. 3. Each codon specifies a particular amino acid that is to be placed in the protein PAGE 367 AAA = _________________ GGA = _________________ AUG = _________________ UAA = _________________ DNA RNA (Transcription) 1. Transcription: a molecule of DNA is copied into an opposite strand of mRNA *Transcription occurs because DNA cannot leave the nucleus, and proteins are made outside the nucleus DNA RNA (Transcription) DNA RNA (Transcription) 2. Steps: a. DNA strands are separated by an enzyme b. An mRNA strand is created from the DNA strand to be copied (remember basepairing rules except . . . ) *G with C *A with U DNA RNA (Transcription) DNA = mRNA = TACCGTTGCAACATT RNA Protein (Translation) RNA Protein (Translation) 1. Translation: the creation of a chain of amino acids from mRNA mRNA = AUGGCAACGUUGUAA Amino acids = RNA Protein (Translation) 2. Translation requires tRNA, which carries amino acids and rRNA, which makes ribosomes 3. Ribosomes floating in the cytoplasm and attached to the ER are the location of protein translation Alleles for diseases come from mutations Mutations: mistakes made during DNA replication or protein synthesis 1. Nucleotide substitution: TATGCA becomes TATTCA 2. Nucleotide addition: TATGCA becomes TATGGCA 3. Nucleotide deletion: TATGCA becomes TATCA All produce frameshift mutations! RNA Protein (Translation) 1. DNA mRNA Protein TACGGCAAACTTACT RNA Protein (Translation) 2. DNA mRNA Protein TACGCCATT RNA Protein (Translation) 3. DNA mRNA Protein TACAAAAAGTGGATC References • http://www.safarikscience.org/biologyhome /7_dna/codon_question.png • http://www.accessexcellence.org/AE/AEP C/WWC/1994/codon_bingo.php