• Difference between RNA and DNA: Each nucleotide contains a different _______ : ribose instead of deoxyribose. Bases are A, G, C, and U (uracyl, not thymine) A pairs with U; G pairs with C
RNA • RNA is ___________ stranded and shorter • RNA is __________ stable than DNA: RNA doesn’t persist in the cell for long (sometimes it exists for a few seconds), whereas DNA can persist for the life of the cell.
Differences between DNA and RNA • __________ • __________ • __________
CENTRAL DOGMA DNA ________ Proteins • 3 different RNA molecules involved in protein synthesis: – M______________ RNA (mRNA) – R______________ RNA (rRNA) – T______________ RNA (tRNA) transcription translation
Transcription: DNA RNA • TRANSCRIPTION: RNA synthesis from DNA. • T___________: making an RNA copy, called m______________ RNA (mRNA), of a small part of the DNA molecule.
Transcription: DNA RNA • Transcription occurs in the N_____________ • mRNA carries the message about what type of protein to make from the DNA in the nucleus to the ribosome • The nucleotide sequences of RNA and DNA are the same (except in RNA uracil is used instead of thymine) • mRNA is synthesized from DNA using base pairing • DNA unwinds in a section
T______________ of RNA from a template strand of DNA • RNA polymerase attaches at the promoter sequence of DNA, and it moves along the DNA, unzipping the strands – this allows for one mRNA molecule to be formed.
• During _____________, a molecule of messenger RNA is formed as a complementary copy of a region on one strand of the DNA molecule
Transcription • Once mRNA is formed, enzymes in the nucleus remove the i__________ (non-coding regions) and leave the exons (expressed segments)
The Genetic Code • Each 3 consecutive bases on the mRNA is a code word, codon, that specifies an amino acid. • The genetic code consists of ______ codons, (4x4x4), but only 61 code amino acids. • Three codons act as signal terminators ( UAA, UAG, UGA ) • One codon, AUG , codes for methionine, and is also the _________ signal for translation.
The Genetic Code • The G__________ Code – every ______ nucleotides on mRNA codes for a particular amino acid (3 at a time) • Code is universal – true for all organisms!
20 Amino Acids There are _____ amino acids – they are like the ‘bricks’, or building blocks to make all proteins
Translation: RNA Protein • T_______________
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