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Protein Synthesis
Period: _____ Name: ______
Biology
Protein Synthesis
The Big Picture
All cells in an organism contain an ______of that organism’s genetic code.
Restate: ______
______
Where do all of the cells in your body come from?
How do specialized cells know which part of the genetic code they are responsible for? ______
______
______
This Process is Called: ______
Engage: Environmental Factors and Gene Expression
- What can you conclude from the data above?
How can genes be activated?
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Protein Synthesis
-Environmental factors
- ______
- ______
- ______
-Chemicals
- ______
- ______
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Protein Synthesis
Summary:
The Big Picture
The Big Picture
DNA Characteristics
Basic Central Dogma: ______ ______ ______
Deoxyribonucleic Acid
- What is Deoxyribonucleic Acid? / Why is it important to living organisms?
- What does DNA give a code for?
- Draw and label 3 forms of DNA.
- What are the 3 main parts of DNA?
- Draw DNA and label the 3 parts. Next circle a nucleotides
DNA Characteristics
- The 3 main parts of DNA make a nucleotide. Nucleotides are the building blocks of DNA.
Draw a nucleotide using:
- Draw DNA and point to where the nitrogen bases are located.
- How do the bases in DNA code for Proteins?
- In the end, what does DNA code for?
- Draw theCentral Dogma
What step did we add?
Would this be true in all Kingdoms?______
Comparing DNA to RNA
mRNA vs. DNA---mRNA is very similar to DNA…But there are differences
- How many strands does DNA have?
mRNA has only 1 strand
- What kind of sugar is found in DNA?
mRNA has a different sugar
- What are the 4 nitrogen bases in DNA?
- What do each pair up with?
mRNA does not have a “T” (thymine) and instead has a “U” for Uracil.
Therefore, what are the 4 nitrogen bases for mRNA?
- What is DNA’s job/function?
mRNA’s job is to code for specific proteins. What do the proteins eventually make?
- Where is DNA always located?
Can DNA ever leave the nucleus?
Because DNA cannot ever leave the ______, it must code for another form to leave the nucleus.
Compare DNA and RNA
Compare DNA and RNA in the space below:
Transcription
TRANSCRIPTION
- Draw the Central Dogma again and determine what DNA codes for next:
- Transcription =
- Is transcription occurring for every gene every second of every day?
- If DNA cannot leave the nucleus, then where must transcription occur?
- ***mRNA is used as a blueprint for converting the message of DNA into proteins
Process of Transcription:
- The DNA double helix unzips
- Complementary RNA nucleotides are paired with one strand of DNA
- The completed RNA molecule detaches from the DNA
- The 2 strands of DNA are rejoined
Reading mRNA
Each codon codes for a specific amino acid. A Codon Chart is used to easily determine the amino acid that each codon codes for.
Practice what do each of these codons code for?
UUA CCC AGA GAC
- If you notice, multiple codons code for the same amino acid.
- Example: Which two codons code for Histidine?
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Protein Synthesis
Compare DNA and RNA
Complete the Venn Diagram using these terms:
- single-stranded
- double-stranded
- thymine
- uracil
- adenine, guanine, cytosine
- found in nucleus
- found in cytoplasm
- stores genetic information
- double helix shape
- goes through replication
- made of 3 base units called codons
- comprised of nucleotides
- ribose sugar
- deoxyribose sugar
Translation
TRANSLATION
- Remember the Central Dogma (page 2):
- Translation =
- Is translation occurring for each gene every second of every day?
-How mRNA codes for proteins using tRNA:
- Key Players in Translation:
Codon =
Anti-codon =
Protein =
Amino Acid=
mRNA=
tRNA=
Translation
- Draw the process of Translation
- Process of Translation:
- mRNA leaves the nucleus and goes to the cytoplasm
- The mRNA strand feeds through the ribosome like a piece of paper through a printer
- Each tRNA carries a specific amino acid
- The tRNA will attach an anti-codon to the codon on the mRNA
- The tRNA will drop-off the amino acid at the ribosome and leave to be re-used
- Another tRNA will attach to the next codon (The next 3 nitrogen bases)
- The next tRNA will drop-off its amino acid with the other amino acids and then leave
- This process continues until a STOP sequence is reached
- All amino acids create a chain of amino acids
- The chain of amino acids makes a protein
Mutations
- Remember by drawing the Central Dogma…AGAIN!
- Can any step in this process be regulated?
- What is the result if any step in this process does not occur correctly?
- What is a mutation?
- Mutation During DNA Replication:
What happens during DNA Replication?
Use the codon chart to answer the following questions:
There are 3 types of mutations that
can occur during DNA replication:
- Substitution
Question: If a codon ACA changes to AUA will the codon change?
Question: If a codon ACA changes to AUA will the amino acid change?
Question: If a codon ACA changes to ACU, will the amino acid change?
Question: If a codon ACA changes to ACU, what will happen to the protein?
Will a change in mRNA change the codon? Circle ( Yes / No )
Will a change in mRNA always change the amino acid? Circle ( Yes / No )
Will a change in amino acid change the protein? Circle ( Yes / No )
- Insertion
Example:THE CAT ATE THE RAT
Insert an A in front of the sentence and divide the letters into codons. What will it read now?
- Deletion
Example: AUG ACA GGU UGU UGA
Amino Acids?
If C is deleted and you keep this sentence in sets of 3 (just as in an mRNA codon), what will it read now?
Order?
Codons?