review: the flow of genetic information in the cell is dna rna protein the sequence of codons in...
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Review: The flow of genetic information in the cell is DNARNAprotein
The sequence of codons in DNA spells out the primary structure of a polypeptide Polypeptides form proteins that cells and
organisms use Animation of Translation
Figure 10.7
DNA molecule
Gene 1
Gene 2
Gene 3
DNA strand
TRANSCRIPTION
RNA
Polypeptide
TRANSLATIONCodon
Amino acid
Transfer RNA molecules serve as interpreters during translation
In the cytoplasm, a ribosome attaches to the mRNA and translates its message into a polypeptide
The process is aided by transfer RNAs
Figure 10.11A
Hydrogen bond
Amino acid attachment site
RNA polynucleotide chain
Anticodon
Each tRNA molecule has a triplet anticodon on one end and an amino acid attachment site on the other
Figure 10.11B, C
Anticodon
Amino acidattachment site
An exercise in translating the genetic code
Startcodon
RNA
Transcribed strand
StopcodonTranslation
Transcription
DNA
Ribosomes build polypeptides
Figure 10.12A-C
Codons
tRNAmolecules
mRNA
Growingpolypeptide
Largesubunit
Smallsubunit
mRNA
mRNAbindingsite
Growingpolypeptide
tRNA
Next amino acidto be added topolypeptide
Table 14.2Types of RNA
Type of RNA Functions in Function
Messenger RNA(mRNA)
Nucleus, migratesto ribosomesin cytoplasm
Carries DNA sequenceinformation to ribosomes
Transfer RNA(tRNA)
Cytoplasm Provides linkage between mRNAand amino acids;transfers aminoacids to ribosomes
Ribosomal RNA(rRNA)
Cytoplasm Structural component of ribosomes
(continued)
4Stage ElongationGrowingpolypeptide
Codons
5Stage Termination
mRNA
Newpeptidebondforming
Stop Codon
The ribosome recognizes a stop codon. The poly-peptide is terminated and released.
A succession of tRNAs add their amino acids to the polypeptide chain as the mRNA is moved through the ribosome, one codon at a time.
Polypeptide