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Ch. 3 Part 4. Protein Synthesis. DNA. Deoxyribonucleic acid Nucleic acid that stores and transmits genetic information from one generation to the next Made of nucleotides 3 parts: deoxyribose sugar, phosphate, nitrogen base 4 bases Adenine, thymine, cytosine, guanine A and G are purines
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Ch. 3 Part 4 Protein Synthesis
DNA • Deoxyribonucleic acid • Nucleic acid that stores and transmits genetic information from one generation to the next • Made of nucleotides • 3 parts: deoxyribose sugar, phosphate, nitrogen base • 4 bases • Adenine, thymine, cytosine, guanine • A and G are purines • T and C are pyrmidines
DNA • A is complementary to T • C is complementary to G
DNA Replication • Making more copies of DNA – needed when making more cells • Steps • Enzyme unzips DNA • Complementary DNA nucleotides match up with the old nucleotides • Enzymes zip 2 pieces back together • ½ is old, ½ is new
DNA Replication • video
DNA vs. RNA • DNA • Sugar is deoxyribose • Double stranded • Thymine • Stays in nucleus • RNA • Sugar is ribose • Single stranded • Uracil • Made in nucleus, leaves to cytoplasm
Transcription • The process of converting the DNA code into an RNA code – in order to make proteins • Steps • Enzyme unzips DNA • RNA nucleotides match with the complementary nucleotides • New mRNA breaks away from DNA and leaves the nucleus to the cytoplasm • DNA zips back up and stays in the nucleus
Transcription • video
Genetic Code • 3 nucleotides make a codon • Codons tell which amino acid goes where in the polypeptide chain • TRANSCRIPTION WITH AN R MAKES RNA • Practice transcribing • DNA says: A – T – T – G – C – A –A – G – G • RNA says:
Translation • Types of RNA • mRNA – messenger – what was made after transcription • tRNA – transfer – carries amino acids to the ribosome to help make proteins • rRNA – ribosomal – makes up ribosomes
Translation • The process of translating the mRNA code into a protein • What are the building blocks of proteins? • Steps • mRNA attaches to ribosome • tRNA brings amino acid (codons and anticodons must match) • Amino acid is dropped off, ribosome slides over on mRNA • Process is repeated
Translation • Must start with a “Start” codon • Must end with a “Stop” codon • Practice Translating • DNA says “ T – A – C –A – C – A – C – G – C • mRNA says • tRNA says • Amino acid says
Translation • video