• The Chapter 14 Homework is due on Sunday,
January 25 at 11:59 pm
• The Chapters 13 and 14 test is on Monday,
January 26
• There will be a pretest at the end of class
tomorrow.
Chapter 14
Central Dogma Overview
Proteins are the links between genotype and
phenotype.
Gene expression, the process by which DNA directs
protein synthesis, includes two stages: transcription
and translation.
DNA
Figure 14.UN01
Central Dogma
RNA
DNA
Transcription
Protein
Translation
• RNA is the bridge between
DNA and protein
synthesis.
• RNA is chemically similar
to DNA, but RNA has a
ribose sugar and the base
uracil (U) rather than
thymine (T).
• RNA is usually singlestranded.
In prokaryotes, translation of mRNA can
begin before transcription has
finished.
DNA
TRANSCRIPTION
mRNA
TRANSLATION
Polypeptide
(a) Bacterial cell
Ribosome
Nuclear
envelope
primary
transcript
TRANSCRIPTION
RNA PROCESSING
DNA
Pre-mRNA
mRNA
TRANSLATION
Ribosome
Polypeptide
(b) Eukaryotic cell