2. The Central Dogma of Biology
Protein synthesis begins with a section of DNA
called a gene which contains the information
for the production of a single protein.
3. The Central Dogma of Biology
DNA
RNA
Protein
Transcription
Translation
4.
5. There are three important differences between the
structure of DNA and the structure of RNA.
1. The pentose sugar found
in RNA is ribose instead of
deoxyribose.
2. The nucleotide thymine
found in DNA is replaced
with uracil in RNA.
3. DNA is a double-helix,
and RNA is a single strand.
10. Transcription
The transcription phase of protein synthesis is
over when mRNA exits the nucleus through a
nuclear pore and enters the cytoplasm.
http://www.youtube.com/watch?v=41_Ne5mS2ls
11. Protein Synthesis: Part Two
Translation
Translation takes place in the cellular cytoplasm. The
process is mediated by large molecular machines called
Ribosomes.
14. Rough Endoplasmic Reticulum: A membranous structure in
the cytoplasm of a cell where proteins destined for export are
assembled.
Vocabulary:
15. Translation starts when a ribosome attaches to a
messenger RNA molecule and begins to assemble
amino acids based on the sequence of codons in the
mRNA molecule.
Translation
16. DNA and RNA use only four
bases to create a code that
determines the sequence of
20 different amino acids in
the final protein.
In order to do this nucleic
acids use three letter
“words” called codons to
indicate each of the amino
acids in the sequence.
What are codons?
19. A third form of RNA called transfer RNA, tRNA, is found in
the cytoplasm.
Translation
20. Translation
The tRNA molecule has a sequence of three nucleotides called
an “anticodon” at one end and a corresponding amino acid at
its opposite end.
Anticodon
Amino Acid
Transfer RNA
22. The ribosome provides a site where tRNA molecules
align with the codons on the mRNA molecule.
Translation
23. Translation
The amino acid on the tRNA is then “transferred” to the
growing protein chain and the tRNA is released back into
the cytoplasm to pick up another amino acid.
http://highered.mcgraw-
hill.com/olcweb/cgi/pluginpop.cgi?it=swf::535::535::/sites/dl/free/0072437316/120077/
micro06.swf::Protein%20Synthesis
24. Eventually the ribosome reaches the end of the mRNA and
protein sequence is complete.
Translation
http://www.youtube.com/watch?v=41_Ne5mS2ls
http://www.youtube.com/watch?v=Jml8CFBWcDs&feature=related