02:19Animation 27.1 Basic principle of recombinant DNA technologyOxford Mastering Biology 牛津基礎生物學1240views2rank
Multiple ChoiceSmall accessory rings of DNA that replicate independently of an organism's genome are called _____.1205views5rank
Multiple ChoiceGene cloning is crucial to any application involving one gene because __________. 631views
Multiple ChoiceWhich of the following enzymes could seal a nick in one strand of a double-stranded DNA molecule by creating a sugar-phosphate bond between the adjacent, unjoined nucleotides? 493views
Multiple ChoiceThe efficiency of cloning, and the ability to generate healthy cloned animals, has been largely hampered by the difficulty of __________. 679views
Multiple ChoiceIn genetic engineering, the highly active plasmid from Agrobacterium tumefaciens is used to __________. 549views
Multiple ChoiceA molecular biologist used a retroviral vector to introduce a gene coding for a certain human enzyme into mouse cells. One cell line was isolated that was able to make the human enzyme, but it had lost the ability to express an endogenous, normally expressed gene in the process. What is the best explanation for these results? 513views
Textbook QuestionWhich of the following is true of a codon? (A) It never codes for the same amino acid as another codon. (B) It can code for more than one amino acid. (C) It can be either in DNA or in RNA (D) It is the basic unit of protein structure2086views
Textbook QuestionWhich of the following would be considered a transgenic organism? a. a bacterium that has received genes via conjugation b. a human given a corrected human blood-clotting gene c. a fern grown in cell culture from a single fern root cell d. a rat with rabbit hemoglobin genes595views
Textbook QuestionRecombinant DNA techniques are used to custom-build bacteria for two main purposes: to obtain multiple copies of certain genes and to obtain useful proteins produced by certain genes. Give an example of each of these applications in medicine and agriculture.511views