1. Bellringer Please answer on your bellringer sheet:
Replicate the following DNA sequence
AGGTATCAG
Please add questions (at least 2 questions per page) and a summary to your DNA Replication Mutation Notes
3 things you learned
2 things you found interesting
1 question you still have

2. Learning Targets (write at the top of your notes)
Compare and contrast the structures and functions of DNA and RNA.
Describe the steps of transcription in synthesizing a protein.
Explain how mRNA can be modified through the process of splicing.
Describe the steps of translation in synthesizing a protein.
Describe the structure of a protein and the functions carried out by proteins in the cell.

3. RNA and Protein Synthesis

4. The Plan…
How does DNA control cell activities if it can’t leave the nucleus?
It sends a messenger! - messenger RNA (mRNA for short)
Remember, DNA (which remember DNA makes up your genes) contains the code for making proteins.
DNA can’t leave the nucleus, so RNA has to help out and actually make the proteins on the ribosomes.

5. 
Ribonucleic Acid
Ribonucleic acid (RNA) - molecule that controls the production of proteins for cells.
A strand of RNA is made of repeating units (monomers) called nucleotides (like DNA)
What makes up a nucleotide?

6. RNA vs. DNA Three differences between RNA and DNA: Single-stranded
Ribose instead of Deoxyribose
Uracil instead of Thymine

7. Checkpoint: RNA vs. DNA DNA RNA  Double strand Deoxyribose
Contains Thymine
Stays in nucleus
Single Strand
Ribose
Contains Uracil
Leaves nucleus

9. Types of RNA  Messenger RNA (mRNA) Transfer RNA (tRNA)
single, uncoiled strand
serves as pattern for assembly of amino acids
Transfer RNA (tRNA)
carries amino acids to the ribosome
single stranded
Ribosomal RNA (rRNA)
globular form
makes up the structure of the ribosome

11. Transcription  Process of making mRNA from a single–strand of DNA.
The nitrogen bases in RNA always bond to their complement on the DNA strand
ADENINE binds to URACIL
GUANINE binds to CYTOSINE

13. Steps in Transcription
Steps in Transcription
The enzyme RNA polymerase “unzips” the complementary strands of DNA into two single strands.
RNA nucleotides bond to a single strand of DNA
The finished mRNA is released and the two DNA strands “re-zip”

14. Steps in Transcription
RNA
DNA
RNA polymerase
Adenine (DNA and RNA)
Cystosine (DNA and RNA)
Guanine(DNA and RNA)
Thymine (DNA only)
Uracil (RNA only)
Transcription animation

15. mRNA Splicing A U G G G C A U U A G C C U A 
Enzymes remove (cut out) introns because they interrupt the coding sequence
INTRONS INTERRUPT … INTRONS OUT !!!
Exons are left behind to be “expressed” (translated) as needed proteins

16. unit of transcription in a DNA strand
Again...
unit of transcription in a DNA strand
exon
intron
exon
intron
exon
transcription into pre-mRNA
snipped out
snipped out
mature mRNA transcript

18. Checkpoint!  Transcribe the DNA strand into RNA:
TAC TCG TCC ATA GGC ATC
AUG AGC UGG UAU CCG UAG

20. 
Protein Synthesis
Bases in mRNA code for the amino acids which will make a functioning protein.
A group of three sequential bases on an mRNA strand is a CODON.

21. 
The Genetic Code
There are a possible 64 CODONS that code for 20 AMINO ACIDS and a START/STOP SIGNAL.
The genetic code is universal among all organisms.

22. The Genetic Code mRNA strand – G C A A C G U U G C U A C U G
First Base
Second Base U C A G
UUU
Phenylalanine
UCU
Serine
UAU
Tyrosine
UGU
Cysteine
UUC
UCC
UAC
UGC
UUA
Leucine
UCA
UAA
Stop
UGA
UUG
UCG
UAG
UGG
Tryptophan
CUU
CCU
Proline
CAU
Histidine
CGU
Arginine
CUC
CCC
CAC
CGC
CUA
CCA
CAA
Glutamine
CGA
CUG
CCG
CAG
CGG
AUU
Isolecine
ACU
Threonine
AAU
Aspargine
AGU
AUC
ACC
AAC
AGC
AUA
ACA
AAA
Lysine
AGA
AUG
Start & Methionine
ACG
AAG
AGG
GUU
Valine
GCU
Alanine
GAU
Aspartic
Acid
GGU
Glycine
GUC
GCC
GAC
GGC
GUA
GCA
GAA
Glutamic Acid
GGA
GUG
GCG
GAG
GGG
mRNA strand – G C A A C G U U G C U A C U G
Amino Acids –
Alanine -
Threonine -
Leucine -
Leucine -
Leucine -

24. 
Steps in Translation
Process of using RNA to assemble amino acids into proteins.
mRNA moves out of the nucleus and attaches to ribosome.
tRNA transports amino acids to the ribosome.

25. Steps in Translation

26. 
Steps in Translation
The anticodon on tRNA bonds to the complementary codon on mRNA.
Amino acids form peptide bonds and form a strand – a polypeptide.
The stop codon on mRNA ends the process and the new protein is released.

27. Steps in Translation
Translation animation

29. Your Turn! Be A Ribosome …
Translate your codons
into amino acids using the codon chart on the next slide:
A U G C A U A G C C U A
Met
His
Ser
Leu
Protein Synthesis Video

30. Codon Chart