Across
- 2. this is a collection of E. coli that has been transformed with recombinant plasmid vectors carrying DNA inserts from a single
- 6. this is a clump of genetically identical bacterial cells growing on an agar plate. Because all the cells in a single colony are genetically identical, they are called clones.
- 7. cellular membranes and other debris of lysed bacteria are found at the bottom of a microfuge tube.
- 9. this has the initials of G.F.P and was originally isolated from the bioluminescent jellyfish, Aequorea victoria. The gene for GFP has recently been cloned. The unique three-dimensional conformation of GFP causes it to resonate when exposed to ultraviolet and give off energy in the form of visible green light.
- 10. this provides a solid matrix to support bacterial growth. Contains nutrient mixture of carbohydrates, amino acids, nucleotides, salts, and vitamins.
- 11. Such a population is called “clonal”. The process of creating a clonal population is called “cloning”. Identical copies of a specific DNA sequence, or gene, can be accomplished following mitotic division of a transformed host cell.
- 12. this is a process of identifying wanted bacteria from a bacterial library.
- 14. this is a liquid and solid media, which is referred to as LB (named after Luria-Bertani) broth and agar are made from an extract of yeast and an enzymatic digest of meat byproducts which provides a mixture of carbohydrates, amino acids, nucleotides, salts, and vitamins, all of which are nutrients for bacterial growth. Agar, which is from seaweed, polymerizes when heated to form a solid gel (very analogous to Jell-O), and functions to provide a solid support on which
- 15. this is a carbohydrate, normally used as source of food by bacteria.
- 17. this is when DNA is extracted from a given cell type, it can be cut into pieces and the pieces can be cloned en masse into a population of plasmids. This process produces a population of hybrid i.e. recombinant DNAs. After introducing these hybrids back into cells, each transformed cell will have received and propagated one unique hybrid. Every hybrid will contain the same vector DNA but a different “insert” dna. If there are 1,000 different DNA molecules in the original mixture,1,000 different hybrids will be formed; 1,000 different transformant cells will be recovered, each carrying one of the original 1,000 pieces of genetic information. Such a collection is called a DNA library. If the original extract came from human cells, the library is a human library. Individual DNAs of interest can be fished out of such a library by screening the library with an appropriate probe.
- 18. this is a circular DNA molecule, capable of autonomous replication, carrying one or more genes for antibiotic resistance proteins.
- 20. this is a protein which provides resistance to the antibiotic ampicillin. The beta-lactamase protein is produced and secreted by bacteria which have been transformed with a plasmid containing the gene for beta-lactamase(bla). The secreted beta-lactamase inactivates the ampicillin present in the growth medium, which allows for bacterial growth and expression of newly acquired genes also contained on the plasmid i.e. GFP.
- 22. this minimizing the possibility of outside bacterial contamination during an experiment through observance of cleanliness and using careful laboratory techniques.
- 23. this is a plasmid containing the GFP sequence and ampicillin resistance gene which codes for Beta-lactamase.
- 24. this is when you apply biology in the real world by the specific manipulation of living organisms, especially at the genetic level, to produce potentially beneficial products.
- 26. this is a gene expression in all organisms is carefully regulated to allow for differing conditions and to prevent wasteful overproduction of unneeded proteins. The genes involved in the transport and breakdown of food are good examples of highly regulated genes. For example, the simple sugar, arabinose, can be used as a source of energy and carbon by bacteria. The bacterial enzymes that are needed to breakdown or digest arabinose for food are not expressed in the absence of arabinose but are expressed when arabinose is present in the environment. In other words when arabinose is around the genes for these digestive enzymes are turned on. When arabinose runs out these genes are turned back off.
- 28. this is a process for separating complex liquid mixtures of proteins or other molecules by passing a liquid mixture over a column containing a solid matrix. The properties of the matrix can be tailored to allow for the selective separation of one kind of molecule from another. Properties include solubility, molecular size, and charge.
Down
- 1. this is the process of cutting and recombining DNA fragments as
- 3. this is when material is released from inside a lysed bacterial cell. Includes proteins, nucleic acids, and all other internal cytoplasmic constituents.
- 4. this is a heavy particles, like bacteria or
- 5. this machine spins a mixture at very high speed to separate heavy and light particles. In this case, centrifugation results in a “pellet” found at the bottom of the tube, and a liquid “supernatant” that resides above the pellet.
- 8. this is a process of passing an inoculating loop with bacteria on it across an agar plate.
- 13. this is when the plasmid is used to move the genes into the bacteria, which contains the gene for beta-lactamase which provides resistance to the antibiotic ampicillin. The beta-lactamase protein is produced and secreted by bacteria which contain the plasmid. The secreted beta-lactamase inactivates the ampicillin present in the LB/agar, which allows for bacterial growth. Only bacteria which contain the plasmids, and express beta-lactamase can survive on the plates which contain ampicillin. Only a very small percentage of the cells take up the plasmid DNA and are transformed. Non-transformed cells, cells that do not contain the plasmid, can not grow on the ampicillin selection plates.
- 16. The manipulation of an organism’s genetic material (DNA) by introducing or eliminating specific genes.
- 19. this is a liquid containing cellular debris that are lighter than the debris in the pellet formed after centrifugation.
- 21. this is when a population of cells is prepared by growth from a single cell, all the cells in the population will be genetically
- 25. culture the bacteria.
- 27. this requires an enzyme to lyse, or break open bacteria cell walls. The enzyme occurs naturally in human tears, acting as a bactericidal agent to help prevent bacterial eye infections. lysozyme gets its name from its ability to lyse bacteria.