Post on 18-Dec-2015
Friday 11/14/2014Take a notes sheet from the front
table. Get out your warm-up sheet & answer the following:What is the complementary
strand for the below DNA strand?
ACTGCACCTGAGCGTATTGACTGACGTGGACTCGCATAACTG
Blast from the Past…1. Who makes proteins in the cell?
2. What are proteins made of?
Protein Synthesis
DNA vs.RNA
• Double-stranded• Deoxyribose• A,G, C, T
• Single stranded• Ribose• A, G, C, U
DNA vs.RNA
NucleusThe office
The Boss never leaves
DNA – The Boss
mRNA – Ms. ReneSecretary
She’s a foreigner
In her language Uhere is no “T”
Protein Synthesis Protein synthesis is the making of
proteins, using the information that is found in DNA.
Proteins are long chains of small molecules called amino acids. Different proteins are made by using a different sequence of amino acids.
Pieces of information in DNA are called genes.
Transcription: means write across
Protein synthesis begins with the DNA molecule. The DNA of this gene will unzip like it does in replication. *The enzyme that separates the DNA strand at a specific gene is helicase.
In protein synthesis, only one strand of the DNA will be used.
Transcription A single strand of mRNA forms and
transcribes (copies) the genetic information from the DNA. This strand of RNA is called messenger RNA or mRNA. *The enzyme that connects and assembles the ribonucleotides is called RNA polymerase
The DNA “zips” closed and remains in the nucleus.
The mRNA will leave the nucleus and travel to a ribosome.
RNA which stands for RIBONUCLEIC ACID is
single stranded, contains a ribose sugar, and
has Uracil instead of Thymine.
Comparing RNA and DNA
Image courtesy of Wikimedia Commons
T
AG
TC
AT
C
A
GG
5’
3’
5’
3’A
TC
AG
TA
G
T
CC
5’
3’
GT CA UAAAAAA TTTTT CCCCC GGGGGG UUUU
3’
5’
DNA Helicase Touch the helicase!
T
AG
TC
AT
C
A
GG
5’
3’
5’
3’A
TC
AG
TA
G
T
CC
5’
3’
GT CA UAAAAAA TTTTT CCCCC GGGGGG UUUU
3’
5’
Assemble your
mRNA strand!!
Hit Me when done!
T
AG
TC
AT
C
A
GG
5’
3’
5’
3’A
TC
AG
TA
G
T
CC
5’
3’
GT CA UAAAAAA TTTTT CCCCC GGGGGG UUUU
3’
5’
RNA polymerase
UC
C
C
A
A
A G
G
U
U
T
AG
TC
AT
C
A
GG
5’
3’
5’
3’A
TC
AG
TA
G
T
CC
5’
3’
A
A
A
U
U
C
C
G
GU
C
3’
5’
Quick Review!
Where does TRNASCRIPTION take place?
NucleusThe office
The Boss never leaves
Where do we get the information to make different
types of proteins?
DNA – The Boss
Who delivers the message to the workers?
mRNA – Ms. ReneSecretary
She’s a foreigner
In her language Uhere is no “T”
Quick Quiz1. What is the name of the enzyme that
unwinds DNA?2. What is the process where a secret
message goes ACROSS the nuclear membrane?
3. What carries the sequence from the DNA out of the nucleus?
4. How many strands are copied on the original DNA molecule?
5. What happens to the DNA once the messenger detaches?
TCCGCGCAGAGCTAG
AGGCGCGUCUCGAUC
Transcribe the following DNA strand: