Paper Protein Synthesis
- Read all the directions first; think twice, cut once.
- This is a visualization assignment. The learning is in the journey, not only the destination.
DNA Synthesis Directions
- From an 8.5" by 11" sheet of paper, cut three paper strips, each 8.5" by 2".
- Cut out the nucleotides on the nucleotide set provided. Some nucleotides have an R on the sugar to denote a ribose (versus deoxyribose).
- Use the nucleotides to build a DNA template strand with the sequence described on the nucleotide sheet. The 5' and 3' ends of the DNA strand are noted below the nucleotide sequence.
- A neat orderly arrangement with proper alignment of the nucleotides will make this assignment easier. Remember that phosphates covalently bond to 3' carbons. The bottoms of the sugar's carbon rings (2' to 3' line) should be parallel.
- Glue the template strand to one 8.5" by 2" strip of paper.
- On a separate paper strip, build the complementary DNA strand using other nucleotides.
- Affix the complementary strand to its paper strip.
- Trim the paper strips so that the nitrogenous bases of the two strands will be able to hydrogen bond.
- Snuggle the two DNA strand together as they would be when the nitrogenous bases are H-bonded to form the double helix. Relax.
Transcription (RNA Synthesis) Directions
- Pretend you are a RNA polymerase and separate the DNA strands.
- Fabricate a mRNA strand to complement the template DNA strand. Remember to use the ribose sugar nucleotides.
- Neatly affix the mRNA strand to the third 8.5" by 2" paper strip paying attention to alignment. Very nice.
- Be sure you bond the DNA strands together again and place your mRNA strand next to the DNA. Picture these polynucleotide strands in the cell nucleus. You are so good!
Translation (Protein Synthesis) Directions
- Cut out the ribosomes, tRNA and amino acid templates from the second sheet provided.
- Move the mRNA out of the imaginary cell nucleus.
- Place the first codon of the 5' end of the mRNA on the small ribosome subunit.
- Move the large subunit above the mRNA and the small subunit. The first codon will be below the right side tRNA outline location of the large subunit ribosome. You have just assembled a ribosome! Take a bow.
- Now you need to find the appropriate tRNA to complement that first mRNA codon.
- Use the codon decoder chart to find the amino acid corresponding to the tRNA anti-codon. Find that amino acid tRNA.
- Place the tRNA on the right side tRNA outline location of the large subunit ribosome. The nucleotides of the mRNA codon and tRNA anti-codon should align.
- Move the mRNA and the tRNA to the second (middle) tRNA outline location of the large subunit ribosome.
- Find the tRNA to match the next mRNA codon. Place that tRNA on the right side tRNA outline location of the large subunit ribosome
- At this point the ribosome would covalently bond the two amino acids. Boom.
- Cut the amino acid from the first tRNA, this tRNA now goes in search of an amino acid. Tape the detached amino acid to the next one.
- Move the mRNA to the left, and repeat steps 5 through 11 for the second amino acid.
- Move the mRNA to the left, and repeat steps 5 through 11 for the third amino acid.
- Move the mRNA to the left, and repeat steps 5 through 10 for the last tRNA.
- Leave the ribosome with the stop codon still on the ribosome.
mRNA Codons Identifying the Amino Acid
The capital letter in the amino acid name, or in ( ), is the single letter abbreviation for that amino acid.
|First letter||Second Letter||Third Letter|
|Methionine (start)||Threonine||lysine (K)||aRginine||G|