Full name:
HW 2 Questions.
Please read the introductory material first or else you will have difficulty
understanding the questions. Then, answer the questions and turn in a hard copy by the due date. If a hard
copy is not turned in, there will be a deduction unless you are absent. If you are absent, please get it to me
by the due date by some other means. (If emailing, I only print the document, so please include your name
in the document, if absent, there will be a deduction!)
1. How does the structure of DNA provide for its replication? How does the
structure of DNA provide for its mutation and evolution?
2. The sequence of DNA is AATTCATACAG. Show the given strand (just
repeat it as is) and the complimentary strand of DNA and also show
proper base pairing and hydrogen bonds (i.e. C=G or C≡G).
3. A few years ago, a young woman claimed her baby was fathered by the
then sixteen year old Justin Bieber. At seventeen, he claimed that he was
not the father and that she was only after his money. This is a true story.
How could you prove the paternity of the child? Be specific and detailed in
your answer.
4. What is chromosomal DNA, non-chromosomal DNA, and how do they
differ?
5. Where is non-chromosomal DNA located in Eubacteria, Archaea, and
Eukarya?
6. Eubacterial chromosomal DNA is generally circular and is not associated
with histone proteins. In general, how does eukaryotic chromosomal DNA
differ? Is the DNA of mitochondria and chloroplasts more similar to
eukaryotic or prokaryotic DNA?
7. a. What is the function of DNA polymerase?
b. Give the names and functions of two other enzymes required for DNA
replication.
8. Briefly explain the Central Dogma in biology.
9. What are the three main types of RNA and what is their function.
10. mRNA is transcribed from the DNA sequence TAC TTT CAA GAG
(spaces added to display codons). Provide the RNA sequence (retain
spaces to show codons).
11. Now translate the mRNA generated above into a polypeptide using the
three letter codes for amino acids.
12. Is there any difference between the nucleotides of tRNA, rRNA, and
mRNA?
13. When is DNA transcribed as tRNA instead of mRNA? (If needed, reread
Homework 2: Microbial Genetics I.)
14. When tRNA binds to mRNA, it binds to with the “anticodon” of tRNA.
What is the region called on mRNA? Why do you think on tRNA it is
called the anticodon?
15. (You do not need to turn this one in, but please do it to prepare yourself
for an exam). Draw a protein being translated from an mRNA. Make it a
big drawing as you will need to include all the RNA types, codons,
anticodons, and the protein factory. Include the names of each RNA,
amino acid, and also indicate where rRNA is.
16. In Jurassic Park, dinosaurs were cloned from blood in mosquitoes trapped
in fossilized amber, leading some to hope that we could clone extinct
animals. Frozen mammoths and fossilized mammoth skin proteins have
been discovered leading some to say that we could translate the skin
proteins to mRNA and then to DNA, allowing us to clone mammoths.
Explain why we cannot clone mammoths from skin proteins knowing what
you now know. (Hint: this is a critical thinking question and we can make
DNA from RNA and RNA from proteins in the lab.)
17. Would it be possible to clone mammoths from the frozen cells that have
been discovered in Russia? (Hint, this is a critical thinking question and
there is frozen DNA in the frozen cells.) Explain your answer.
18. Ribosomes are named by their sedimentation rate in an ultracentrifuge.
Larger ribosomes move more quickly towards the bottom of the centrifuge
tube. Prokaryotic ribosomes differ from eukaryotic ribosomes as they are
smaller at 70S compared to eukaryotic at 80S. If someone were to find a
drug that selectively bound one ribsome and not the other, would this be a
potent antimicrobial drug? Explain your answer?
19. A child got a severe infection after badly crashing his bike to avoid running
over a cat. He was taking a high dose of antibacterial drugs for weeks.
His infection came under control, though he was lethargic and had little
energy. Explain how 70S ribosomes might explain his lethargy and little
energy.
20. What are the five types of mutations? Which is the least and most
severe change to the DNA?