Unit 6 Reflection

This unit focused on the field of biotechnology, which is the use and manipulation of living things and their parts for human benefit. There are 4 main applications of biotech: industrial and environmental, agricultural, medical/ pharmaceutical, and diagnostic research. In the industrial and environmental field, fermentation as well as biofuels (using cellulase to break down cellulose into simple sugars as well as fermentation to produce alcohol for the fuel). Medical and pharmaceutical biotechnology includes gene therapy--both germ line gene therapy and somatic gene therapy. Gene therapy is inserting a copy of a healthy gene into a person who has a defective copy of that gene. An example of agricultural biotechnology is classical breeding, where individuals with a certain desired trait are bred several times. GMO, or transgenic organisms, have had recombinant DNA inserted into them. I felt that I understood this overview of biotechnology fairly well. There are also certain ethical questions that are asked of the field of biotechnology, called bioethical questions. Bioethics is the study of decision-making as it applies to certain advances in biology and medicine.

One technology in the field of biotech is recombinant DNA (rDNA). It is taking DNA from one organism and inserting it into another. The first step in this is to identify the gene of interest and the location and the sequence. Restriction enzymes are very specific enzymes which cut DNA whenever they read a specific sequence. They make a jagged cut and create two "sticky ends" that can bond with other DNA. Plasmids, which are circular DNA in bacteria, are naturally resistant to a certain antibiotic. I felt that this topic was one of my strengths, especially after doing the recombinant DNA lab, where we modeled inserting the insulin gene into a plasmid that was resistant to tetracycline, and only the bacteria with the plasmid would survive.

Model of recombinant plasmid

Another technology of biotech is PCR (Polymerase Chain Reaction), which is a procedure that creates millions of copies of a sequence of DNA so that that sequence can be analyzed. The DNA is denatured with heat, primers are annealed to the single-stranded DNA above and below the gene, DNA Polymerase are extended, and the process is repeated. Gel electrophoresis uses electricity to separate DNA fragments based on size, since the larger fragments travel more slowly than the smaller fragments. 

In the pGLO lab , we added a plasmid which contained GFP (Glowing Fluorescent Protein) to E.coli. There were 4 plates: -pGLO LB, -pGLO LB/amp, +pGLO LB/amp, and +pGLO amp/ara. The bacteria on the -pGLO plate formed a carpet of colonies. The -pGLO LB/amp plate had no growth. The +pGLO LB/amp plate had roughly 130 colonies, and the +pGLO LB/amp/ara had 150 colonies and glowed green under UV light. This lab helped me understand the process We also did the candy electrophoresis lab, where we put four reference dyes (Blue 1, Red 40, Yellow 6, Yellow 5) into four wells. Then we extracted dyes off of candies, such as purple skittles, blue m&m's, red skittles...etc and inserted them into remaining wells. We were able to compare the size of the fragments and identify if any of the reference dyes were present in the candies. From this lab, I was able to better understand how gel electrophoresis works and how to analyze the results. 

Candy Electrophoresis Lab 

I want to learn more about gene therapy and the advances in this technology that are being made today that are getting us closer to the "GATTACA" world. I also wonder about the ethical questions that go along with so many of these advances in gene therapy. 

This year, one of my new year's goals was to actively take charge of learning in biology by participating in class and acknowledging what I don't understand of the material. I am definitely putting more thought into writing relate and reviews and I am also including diagrams in my vodcast notes to help me understand the material better. My next steps are to think about what I don't understand and ask specific questions.