A new class of enzymes was discovered in the late 1960s. These enzymes cut through the two strands of a DNA molecule in such a way that each strand is left with several unpaired nitrogen-containing bases. Such DNA fragments can then be joined and sealed to form an intact molecule. In effect, a new DNA molecule can be designed and constructed. This process is known as genetic engineering. Genetic engineering involves inserting segments of DNA taken from one organism into the DNA of another organism. 1. A species is defined as a group of organisms that can mate and produce fertile offspring in nature. Consider that genetic engineering has taken human genes and inserted them into bacterial DNA molecules. Explain why this product of genetic engineering is called recombinant DNA. 2. Bacteria divide very rapidly so that multiple copies of the human gene are produced in a very short time. Hopefully, the human genes will be active and produce proteins. These proteins can then be isolated and harvested. For example, genetic engineering is used to enable bacteria to produce a human growth hormone. How does this demonstrate that genetic engineering can benefit humans? 3. Consider a plant species that is resistant to certain pests. This resistance is due to a gene for pest resistance. Describe how genetic engineering can be used to make another plant species resistant to these pests.
Added by Michael W.
Close
Step 1
Step 1: Genetic engineering involves cutting and joining genetic material from different organisms to create new combinations, known as recombinant DNA. Show more…
Show all steps
Your feedback will help us improve your experience
Suman K and 69 other Biology educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Experimental manipulation of DNA: Scientists discovered that naturally occurring enzymes in bacteria could cut DNA into pieces. These restriction enzymes were isolated and are now used routinely to cut DNA at specific locations along the sequence. This exercise will enable you to visualize how this works and how this technique can be applied to disease analysis. You will have a piece of paper that has DNA strands on it, represented by this: E P B H B The letters E, P, B, and H along the DNA signify specific nucleotide sequences where restriction enzymes cut the DNA; for example, E is a restriction enzyme called Eco RI, and it cuts between the G and the A in the following sequence GAATTC. The other letters represent different restriction enzymes. 1. Each line on the DNA strand marks 1 inch. If this piece of paper represents a piece of DNA and 1 inch corresponds to 1 KB (kilo bases or 1,000 base pairs of DNA), what is the length of your DNA in KB?
Jenny W.
48. Suppose a restriction enzyme recognizes the 6-base sequence below in a double strand of DNA. Between which 2 nucleotides on each strand would the enzyme have to cut to produce a fragment with "sticky ends" that are indicated in the bases below? AAGCTT TTCGAA a. GC b. CT c. AA d. AG 49. To produce genetically engineered bacteria that make a human protein like Insulin, which of the following steps does a scientist have to take first? a. insert the human gene for the protein Insulin into a plasmid b. extract the protein from the bacterial culture that is making insulin c. use a restriction enzyme to cut out the gene from human DNA d. none of the above 50. One function of gel electrophoresis is to a. separate DNA fragments by weight b. cut DNA into fragment lengths c. recombine DNA with other genes d. extract DNA 51. Combining genes from different sources into a single DNA molecule is known as a. DNA fingerprinting b. PCR technique c. Vectoring d. Recombinant DNA technology 52. What is the advantage of producing transgenic plants? a. increasing herbicide resistance b. using more pesticides c. producing clones d. studying human genes 53. On an electrophoresis gel, Band B is closer to the positive end of the gel than is Band A. Which of the following statements is true? a. Band B is more positively charged than Band A b. Band B moved faster than Band A c. Band A is smaller than Band B d. Band B consists of larger DNA fragments than does Band A
Describe the process of molecular cloning. a. The foreign DNA and plasmid are cut with the same restriction enzyme and DNA is inserted within the lacZ gene, whose product metabolizes lactose. The foreign DNA and vector are allowed to anneal. The vector is transferred to a bacterial host that is ampicillin sensitive and those with a disrupted lacZ gene show inability to metabolize X-gal. b. The foreign DNA and plasmid are denatured using high heat, and DNA is inserted within the lacZ gene, whose product metabolizes glucose. The foreign DNA and vector are allowed to anneal. The vector is transferred to a bacterial host that is ampicillin sensitive and disrupted lacZ gene will metabolize X-gal c. The foreign DNA and plasmid are cut with the same restriction enzyme and DNA is inserted randomly in the plasmid. The foreign DNA and vector are allowed to anneal. The vector is transferred to a bacterial host that is ampicillin sensitive and the disrupted lacZ gene shows inability to synthesize X-gal. d. The foreign DNA and plasmid are cut with the same restriction enzyme and DNA is inserted within the lacZ gene, whose product metabolizes lactose. The foreign DNA and vector are allowed to anneal. The vector is transformed into a viral host that is ampicillin sensitive and the disrupted lacZ gene show inability to synthesize X-gal.
Recommended Textbooks
Biology for AP Courses
Objective Biology for NEET
Introduction to General, Organic and Biochemistry
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD