DNA RNA Protein Synthesis DNA vs RNA a
- Slides: 10
DNA & RNA Protein Synthesis
DNA vs RNA
a. DNA - carries the blueprint for the order of amino acids to be produced during protein synthesis. b. Messenger RNA (m. RNA) - copies the DNA molecule in the nucleus during transcription and goes into the cytoplasm and attaches itself to a ribosome. One 3 letter unit in an m. RNA chain is called a codon. c. Transfer RNA (t. RNA) - drops off amino acids it is coded to carry at the ribsome. The 3 letter code is complementary to m. RNA and this 3 letter code is called the anti-codon d. Ribosome (r. RNA) - this is where protein synthesis occurs. (Where the protein is assembled) http: //www. wiley. com/college/pratt/0471393878/student/animations/d na_replication/index. html http: //www. bioteach. ubc. ca/Teaching. Resources/Molecular. Biology/DNA Replication. swf
Determine the amino acids coded for by a strand of DNA 1. Determining codons from a strand of DNA Consider the following strand of DNA read from left to right: TTATGCTCCTAA When complementary base pairing occurs the following strand of m. RNA is obtained. AAUACGAGGAUU The codons are read three letters at a time from the transcribed m. RNA. The codons are: AAU ACG AGG AUU 2. Determining amino acids from m. RNA codons Find the codons in the table of m. RNA codons below and the amino acids they code for. AAU -Asparagine ACG - Threonine AGG - Arginine AUU -isoleucine
5 steps in protein synthesis -DNA serves as a code for proteins -Transcription occurs. One strand of DNA serves as a template (blueprint) for the formation of m. RNA. -after transcription, the newly formed m. RNA goes into the cytoplasm and attaches to a ribosome. -t. RNA which carry specific amino acids, have anticodons which bind complementarily with the m. RNA codons -The ribosome moves along the m. RNA strand reading each codon. The t. RNA anticodon bonds to its complementary codon. The amino acid carried by the t. RNA is bonded to the polypeptide. The ribosome moves down the m. RNA strand one codon at a time releasing a t. RNA as it does and making room for another t. RNA carrying an amino acid to join the m. RNA. http: //www. youtube. com/watch? v=1 PSwh. TGFMxs&feature=related DNA QUIZ QUESTIONS
RNA Transcription http: //www-class. unl. edu/biochem/gp 2/m_biology/animation/gene_a 2. html http: //www. stolaf. edu/people/giannini/flashanimat/molgenetics/transcription. swf
Gene Expression: DNA- Proteins • Transcription = DNA → RNA • Translation = RNA → protein
