Name: ___________________________________ Date: _________________
Biology ~ DNA Workshop Period: ________________
The Central Dogma: DNA Workshop
Background:A dogma is an unchanging or unbreakable rule. We have learned that cells have a central dogma that can not be changed. DNA will always be transcribed into RNA and then translated in proteins.
Throughout this chapter we have explored the processes of this central dogma. By now, we know that without the production of proteins our bodies and cells would not be able to function. Many
researchers have paved the way to our understanding of this knowledge; and (hopefully) you will start to see how this information can be combined with a lot of the topics that we have studied throughout the year.
Objective:
The purpose of this lab is to explore the main steps of the central dogma of cells. We will use the DNA Workshop website to simulate the events of DNA replication, transcription, and translation.
Procedure:
Please go to the following website in order to complete this lab:
http://www.pbs.org/wgbh/aso/tryit/dna
You will need to CAREFULLY read the text at each step. Make sure to answer
any questions or draw any pictures BEFORE you move on, click “ok”, etc. or you
will have to start the activity over!
Click on “DNA Workshop Activity” to complete the following questions.
Your first job is to simulate REPLICATION. Select “DNA Replication” and do the
activity. Answer the questions at the end of each step.
1. Draw the original, “parent” strand of DNA.
2. How many strands of DNA do you begin with? ____________________________
Click on “unzip”, read and answer questions 3 & 4.
3. When the DNA strand is unzipped, what does it resemble? _______________________ 4. What breaks the rungs of DNA? _______________________________
Click “ok” then answer questions 5 & 6.
5. What letters are on the four base pairs for replication? ___________________________ 6. Which letter does A match up with in replication? __________________________
Replicate the DNA, answer question 7, then click “ok” and answer questions 8 – 10.
7. How many base pairs are found in real DNA? ________________________
When you finish the DNA replication, click on “Protein Synthesis” at the top right
corner. You will now be simulating TRANSCRIPTION. Click “unzip”, read the
box, click “ok”, and then answer questions 1 – 4.
1. Where in the cell is transcription taking place?________________________
2. What happens in transcription? __________________________________________________ 3. What letters are on the four base pairs for transcription? __________________________ 4. Which letter does A match up with in transcription? ___________________________
Match your nitrogen bases, read and then answer questions 5 – 9.
5. After matching the base pairs, you have created a short segment of ____________________? 6. How long would a real RNA molecule be? ___________________________________ 7. What does mRNA stand for? ____________________________________
8. Draw what your mRNA segment looks like. (Make sure to only draw the mRNA!)
9. How many codons does your mRNA consist of? ___________________________
Read question 10. Click “ok” and watch where the red “you are here” dot moves.
10. After transcription is complete, where does the mRNA strand travel? ____________________
You will now replicate TRANSLATION. Answer questions 1 – 5.
1.
Where does translation take place? ____________________________2.
The mRNA strand is read by grouping how many bases at one time? ___________________3.
What are these groups of bases called? ___________________
Read the box and answer questions 6 – 8.
6.
What organelle is linked up with the mRNA during translation? ______________________7.
What is the complimentary set of bases located on the tRNA called? __________________8.
What is attached to the end of a tRNA molecule besides the complimentary bases? _________________________
Click “ok” and answer questions 9 & 10.
9.
Draw the 1st anticodon that would be needed to build this amino acid chain.10.
What amino acid does the 1st tRNA carry? _____________________________
Grab the second tRNA that would be needed by your mRNA strand then answer
questions 11 – 13.
11.
What happens to the first tRNA? _____________________________12.
What is the 2nd anticodon that is needed to build this amino acid chain? ________________________________ Add it to the chain in question 9.
13.
What amino acid does the 2nd tRNA carry? _____________________Add it to the chain inquestion 10.
Click “ok”, grab the third tRNA that would be needed by your mRNA strand, read
the box, and then answer questions 14 – 18.
14.
How long is your protein under construction? _____________________15.
How long will this chain get? _________________________________16.
What was the 3rd anticodon needed to build your amino acid chain? ________________ Add itto the chain in question 9.
17.
What amino acid did the 3rd tRNA carry? _____________________ Add it to the chain inquestion 10.
Return to the home page by closing the window.
Scroll down until you find “Watson and Crick describe structure of DNA”.
Click on that option and answer the following questions.
1. What were Watson and Crick trying to do? 2. What had Franklin discovered?
3. Who showed Watson the X-Ray diffractions? Did he have permission?
4. Using this information, what did Watson and Crick propose?
5. The discovery of _____________________ has been called the most important biological work of the last 100 years.
6. Watson, Crick and Wilkins won the ___________________ for physiology/medicine.
7. Who else should have been included?
Return to the home page by pressing the back key.
Scroll down until you find “Amino Acids are Created in the Laboratory”.
Click on that option and answer the following questions.
1. Explain how Urey believed the earth’s atmosphere developed.
4. Why are amino acids important?
Return to the home page by pressing the back key.
Scroll down until you find “DNA Replication”.
Click on that option and answer the following questions.
1. The code that holds all the information needed to make and control every cell within a living organism is _________________________________.
2. DNA resembles _________________________.
3. ________________ and ___________________ form the sides of the DNA. 4. The bases form the _______________________ of the ladder.
5. The four bases are: _____________ ______________ _____________ _____________ .
6. A nucleotide is made up of ___________________, _________________ and a _________________
7. ________________ are the units which, when linked to sugar and phosphate, make up one side of a DNA ladder.
8. The DNA molecule is unzipped by __________________.
9. Cytosine (C) will pair to _____________ and adenine (A) will pair with ___________________.
Return to the home page by pressing the back key.
From here scroll down until you find “All Wound Up”.
Click on that option and answer the following questions.
1. A single strand of DNA forms a ____________
2. The DNA is wrapped around spools of a protein called ______________ 3. Fruit flies have ____________ chromosomes.
From here scroll down until you find “Protein Synthesis”.
Click on that option and answer the following questions.
1. What is the purpose of protein synthesis
