click below
click below
Normal Size Small Size show me how
Chapter 10 Bio
Nucleic Acids & Protein Synthesis
| Term | Definition |
|---|---|
| DNA | Deoxyribonucleic Acid |
| Double Helix | shape of DNA |
| Purines | Adenine and Guanine |
| Pyrimidines | Cytosine and Thymine |
| replication | process of copying DNA |
| Helicases | enzymes that separate base pairs |
| DNA Polymerase | enzymes that bind to the separated chains of DNA |
| Complimentary Base Pairs | C-G, A-T |
| 1 in 1000000000 (1 billion) | amount of error in paired nucleotides after proofreading |
| RNA | Ribonucleic Acid |
| DNA nucleotide | sugar (deoxyribose), phosphate (phosphorus), and 1 nitrogen base (adenine, guanine, cytosine, thymine) |
| RNA nucleotide | sugar(ribose), phosphate, nitrogen containing base |
| messenger RNA (mRNA) | carries genetic info from DNA to cytoplasm; single uncoiled chain |
| transfer RNA (tRNA) | binds to specific amino acids; 45 varieties; single chain of approx. 80 RNA nucleotides; hairpin shape |
| ribosomal RNA (rRNA) | most abundant; globular form; makes up the ribosome where proteins are made |
| transcription | process by which genetic info is copied from DNA to RNA |
| mRNA, tRNA, rRNA | products of transcription (transcripts) |
| protein synthesis | production of proteins; amount/type of protein determine structure & function of the cell |
| proteins | polymers; made of 1+ polypeptides; may contain 1000s of amino acids |
| amino acids | 20; determines how the polypeptides will twist and fold into the 3D protein structure |
| genetic code | correlation between a nucleotide sequence and an amino acid sequence; used by most organisms to translate mRNA transcripts into proteins |
| codon | 3 mRNA nucleotides; codes for specific amino acids; some do not code at all( signal for translation of an mRNA to start/stop |
| AUG | start codon |
| UAA,UAG, UGA | stop codon |
| translation | process of assembling polypeptides from info encoded in mRNA; begins when mRNA leaves the nucleus through pores in the nuclear membrane |
| anticodon | the loop opposite of the site of the amino acid attachment bears a sequence of 3 nucleotides; complementary; pairs with the mRNA codon |
| ribosomes | composed of rRNA and proteins and are free in the cytoplasm and attached to the endoplasmic reticulum |
| binding sites | one holds and mRNA transcript so that its codons are accessible to rRNA molecules; the other two hold tRNAs whose anticodons pair with mRNA codons |
| DNA vs. RNA | in RNA sugar is ribose, thymine is NOT present, but uracil is, and it is single stranded |
| adenine and guanine | made of two rings of carbon; purines |
| cytosine and thymine | made of one ring of carbon; pyrimidines |