All Free Biology MCQs with Answers
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19844 questions · page 532 of 1985
5311. Pieces of DNA are jointed by:
- A. Chimaeric DNA
- B. DNA ligase
- C. Plasmids
- D. Endonucleases
Explanation: DNA ligase enzyme seals the foreign piece ofDNA into the vector.
Correct answer: DNA ligase5312. Match recombinant DNA with one of the followings:
- A. Chimaeric DNA
- B. DNA ligase
- C. Plasmids
- D. Endonucleases
Explanation: Recombinant DNA is also called chimaeric DNA.
Correct answer: Chimaeric DNA5313. Recombinant DNA are expressed in:
- A. Man
- B. Virus
- C. Bacteria
- D. None of the above
Explanation: Bacterial cells take up recombinant plasmid,especially, if they are treated with calcium chloride to make them more permeable.
Correct answer: Bacteria5314. The chemical that makes the bacterial membrane permeable is:
- A. NaCl
- B. CaCl2
- C. Na2CO3
- D. CaCO3
Explanation: Bacterial cells take up recombinant plasmid,especially, if they are treated with calcium chloride to make them more permeable
Correct answer: CaCl25315. The single standard nucleotide sequence that hybridize into certain piece is:
- A. Clone
- B. Probe
- C. RFLP
- D. Endonuclease
Explanation: A probe is a single stranded nucleotide sequence that will hybridize (pair) with a certain pieceof DNA
Correct answer: Probe5316. Which of the followings form genomic library?
- A. Bacteria
- B. Bacteriophage
- C. Segment of DNA
- D. None of the above
Explanation: A genome is a full set of genes of an individual. A genomic library is a collection ofbacterial or bacteriophage clones, each clone containing a particular segment ofDNA from the source cell.
Correct answer: None of the above5317. PCR technique was developed by:
- A. Kary Mullis
- B. Hamilton
- C. Sanger
- D. Maxam
Explanation: Kary B. Mullis developed the polymerase chain reaction (PCR) in 1983.
Correct answer: Kary Mullis5318. Match target DNA with one of the followings:
- A. Primer DNA
- B. Recombinant DNA
- C. DNA polymerase
- D. Thermocycler
Explanation: Before carrying out PCR, primers - sequences of about 20 bases that are complementaryto the bases on either side of the "target DNA" - must be available. The primers are neededbecause DNA polymerase does not start the replication process; it only continues orextends the process. After the primers bind by complementary base pairing to theDNA strand, DNA polymerase copies the target DNA.
Correct answer: Primer DNA5319. The enzyme extracted from Thermus aquaticus is:
- A. Primer DNA
- B. Recombinant DNA
- C. DNA polymerase
- D. Thermocycler
Explanation: DNA polymerase is a temperature-insensitive (thermostable) enzyme extractedfrom the bacterium Thermus aquaticus
Correct answer: DNA polymerase5320. The steps involved in DNA finger printing:
- A. RFLP
- B. Probes
- C. PCR
- D. All of the above
Explanation: The genome is treated with restriction enzymes, which resultsin a unique collection of different-sized fragments. Therefore, restriction fragmentlength polymorphism (RFLPs) exists between individuals. The use of probes for genetic markers produces adistinctive pattern that can be recorded on X-ray film. PCR amplification and analysis can be used (1) to diagnose viral infections, geneticdisorders, and cancer (2) in forensic laboratories to identify criminals; and (3) todetermine the evolutionary history of the human population.
Correct answer: All of the above