Lab 14 Biomolecular Techniques
Pre-Lab Questions
1. Transformation, conjugation, and transduction were discovered in the laboratory. How
important are these mechanisms of genetic recombination in nature?
Evolution is supported by these processes. Bacteria can develop new functions by
transforming once they receive that marker. Conjugation allows bacteria to transfer
genetic information to other bacteria. Transduction includes vectors picking up
information from bacteria and transferring them to other bacteria.
2. Use the internet to investigate DNA fingerprinting. What is this process, and how is it
used in criminal forensics?
DNA fingerprinting is done by gel electrophoresis. This process separates DNA strands
based on size. When molecules are placed into the cell they migrate toward the opposite
charge. Size is measured by distance, because larger molecules move more slowly.
Criminal forensics uses this process to match a person’s DNA sample to evidence
collected. Each person has unique DNA strands, so comparing the lengths of DNA can
determine the individual.
3. How can plasmids be used to manufacture proteins such as insulin for diabetic patients,
or antibiotics for bacterial infections?
This is possible by injecting DNA into bacteria, placing the bacteria on an antibiotic plate,
and shocking the bacteria so it absorbs the DNA and plasmids are transferred to it.
These bacteria are now antibiotic-resistant and will form colonies which can be used to
produce proteins.
4. Research a genetic disease that may be cured through the use of genetic engineering.
What techniques are being explored to correct the problem? How do concerns of
designer embryos stem from this technology?
Certain forms of genetic blindness could be cured by genetic engineering. This could be
possible by inactivating a part of the DNA in the retina. Concerns from this come from
the fact it would be more than just babies being “designer.” Babies, children, and adults
would be able to undergo this process. Also, genetic engineering could change an
individual’s own unique cells.
, Experiment 1: DNA Extraction
Post-Lab Questions
1. Which DNA bases pair with each other? What does it mean that DNA bases are
complementary?
Adenine + Uracil
Adenine + Thymine
Cytosine + Guanine
DNA bases are complementary because only specific bases can bond with each other.
2. How is DNA information used to make proteins?
DNA is transcribed into mRNA. Next, it undergoes translation to become a protein.
3. What is the purpose of the following reagents in the experiment?
a. Salt (in the DNA Extraction Solution): Neutralizes DNA to allow precipitation
b. Detergent (in the DNA Extraction Solution): Break down membrane
c. Ethanol: Creates ionic bonds between the salt and the phosphate from DNA
which causes the DNA to precipitate
4. What else might be in the ethanol/aqueous interface? (Hint: Which molecules are similar
to DNA?)
RNA.
5. What is the texture and consistency of the DNA that you extracted?
The DNA I extracted had the consistency of slime.
6. Is the DNA soluble in the aqueous solution or alcohol?
Aqueous solution, because it is polar.
Pre-Lab Questions
1. Transformation, conjugation, and transduction were discovered in the laboratory. How
important are these mechanisms of genetic recombination in nature?
Evolution is supported by these processes. Bacteria can develop new functions by
transforming once they receive that marker. Conjugation allows bacteria to transfer
genetic information to other bacteria. Transduction includes vectors picking up
information from bacteria and transferring them to other bacteria.
2. Use the internet to investigate DNA fingerprinting. What is this process, and how is it
used in criminal forensics?
DNA fingerprinting is done by gel electrophoresis. This process separates DNA strands
based on size. When molecules are placed into the cell they migrate toward the opposite
charge. Size is measured by distance, because larger molecules move more slowly.
Criminal forensics uses this process to match a person’s DNA sample to evidence
collected. Each person has unique DNA strands, so comparing the lengths of DNA can
determine the individual.
3. How can plasmids be used to manufacture proteins such as insulin for diabetic patients,
or antibiotics for bacterial infections?
This is possible by injecting DNA into bacteria, placing the bacteria on an antibiotic plate,
and shocking the bacteria so it absorbs the DNA and plasmids are transferred to it.
These bacteria are now antibiotic-resistant and will form colonies which can be used to
produce proteins.
4. Research a genetic disease that may be cured through the use of genetic engineering.
What techniques are being explored to correct the problem? How do concerns of
designer embryos stem from this technology?
Certain forms of genetic blindness could be cured by genetic engineering. This could be
possible by inactivating a part of the DNA in the retina. Concerns from this come from
the fact it would be more than just babies being “designer.” Babies, children, and adults
would be able to undergo this process. Also, genetic engineering could change an
individual’s own unique cells.
, Experiment 1: DNA Extraction
Post-Lab Questions
1. Which DNA bases pair with each other? What does it mean that DNA bases are
complementary?
Adenine + Uracil
Adenine + Thymine
Cytosine + Guanine
DNA bases are complementary because only specific bases can bond with each other.
2. How is DNA information used to make proteins?
DNA is transcribed into mRNA. Next, it undergoes translation to become a protein.
3. What is the purpose of the following reagents in the experiment?
a. Salt (in the DNA Extraction Solution): Neutralizes DNA to allow precipitation
b. Detergent (in the DNA Extraction Solution): Break down membrane
c. Ethanol: Creates ionic bonds between the salt and the phosphate from DNA
which causes the DNA to precipitate
4. What else might be in the ethanol/aqueous interface? (Hint: Which molecules are similar
to DNA?)
RNA.
5. What is the texture and consistency of the DNA that you extracted?
The DNA I extracted had the consistency of slime.
6. Is the DNA soluble in the aqueous solution or alcohol?
Aqueous solution, because it is polar.
