The enzyme used in the polymerase chain reaction is a :
(1) DNA dependent RNA polymerase
(2) RNA dependent DNA polymerase
(3) DNA dependent DNA polymerase
(4) RNA dependent RNA polymerase
An important limitation to the use of Agrobacterium tumefaciens is that it can not:
1. infect dicots
2. be genetically modified
3. be cultured on a nutrient medium
4. infect crop plants such as wheat and corn
Identify a character that is not desirable in a cloning vector:
1. an inactive promoter
2. an origin of replication site
3. selectable markers such as genes for antibiotic resistance
4. one or more unique restriction endonuclease sites
Restriction enzymes are synthesized by:
(1) bacteria only
(2) yeast and bacteria
(3) eukaryotic cells only
(4) all kinds of cells
A cloning vector has two antibiotic resistance genes- for tetracycline and ampicillin. A foreign DNA was inserted into the tetracycline gene. Non-recombinants would survive on the medium containing :
1. ampicillin but not tetracycline
2. tetracycline but not ampicillin
3. both tetracycline and ampicillin
4. neither tetracycline nor ampicillin
A molecular technique in which DNA sequences between two oligonucleotide primers can be amplified is known as:
1. southern blotting
2. northern blotting
3. polymerase chain reaction
4. DNA replication
Agrobacterium tumefaciens is
1. a disease in humans that causes loss of sight
2. a bacterium that can be used to introduce DNA into plants
3. a fungi that is used to produce antibiotics in large amounts
4. a disease in humans that causes loss of weight
Vectors are
1. molecules that degrade nucleic acids
2. molecules that help in replication
3. molecules that are able to covalently bond to and carry foreign DNA into cells
4. molecules that protect host cells from invasion by foreign DNA
Bacterial cells protect their own DNA from degradation by restriction endonucleases by
1. methylating the DNA at the sites that the enzyme recognizes
2. deleting all recognition sites from the genome
3. not producing any restriction endonucleases
4. having anti restriction endonucleases
Which of the following enzyme is used to covalently bond foreign DNA to a vector plasmid?
1. DNA polymerase
2. Restriction endonuclease
3. DNA ligase
4. DNA helicase
The piece of equipment, that introduces DNA into cells via DNA-coated microprojectiles is known as
1. laser
2. DNA probe
3. gene gun
4. inoculating needle
Electroporation is:
1. the process of separating charged molecules through a gel maintained in an electric field
2. the process of combining foreign DNA to an electrically charged vector molecule
3. the process of introducing DNA into cells by the application of high voltage pulses
4. the process of introducing DNA into plant cells by the application of PEG
A gene carried by recombinant DNA is cloned when:
1. The host bacterium divides by binary fission
2. It is transcribed
3. It is fragmented by restriction enzymes
4. It is hybridized
A piece of nucleic acid used to find a gene, by forming a hybrid with it, is called a:
1. Probe
2. Vector
3. Restriction sequence
4. Retrovirus
Restriction enzymes are synthesized by:
1. Bacteria only
2. Yeast and Bacteria only
3. Eukaryotic cells only
4. All kinds of cells
Bacterial resistance to antibiotics is a genetic trait carried in the bacterial:
1. Intron
2. Chromosome
3. Plasmid
4. Centromere
Which of the following tools of recombinant DNA technology is INCORRECTLY paired with one of its uses?
1. restriction endonuclease - production of DNA fragments for gene cloning.
2. DNA polymerase - copies DNA sequences in the polymerase chain reaction.
3. reverse transcriptase - production of B DNA from mRNA.
4. electrophoresis - RLFP analysis
Which of the following is not part of the normal process of cloning recombinant DNA in bacteria?
1. restriction endonuclease digestion of cellular and plasmid DNAs.
2. production of recombinant DNA using DNA ligase and a mixture of digested cellular and plasmid DNAs.
3. separation of recombinant DNAs by electrophoresis using the Southern technique to determine where the desired recombinant migrates.
4. transformation of bacteria by the recombinant DNA plasmids and selection using ampicillin .
Mark the correct statement for pBR322 as a plasmid vector
I. Contains relaxed origin of replication.
II. Two genes coding for resistance to antibiotics have been introduced.
III. There are single recognition sites for a number of restriction enzymes at various points.
IV. Insertional inactivation is a useful selection method for identifying recombination vectors with insert.
1. I, II, III & IV
2. I, II only
3. II, III only
4. II only
If two enzymes A and B are used for restriction mapping of 9 kb molecule, cleavage with A gives fragments of 2 and 7 kb and B gives fragments and 3 and 6 kb. If A and B cut at opposite end of molecule what will be the length of fragment after double digestion?
1. 2 kb, 3 kb, 4 kb.
2. 1 kb, 2 kb, 6 kb.
3. 3 kb, 3 kb, 3 kb.
4. 2 kb, 2 kb, 5 kb.
How does a bacterial cell protect its own DNA from restriction enzymes?
1. By adding methyl groups to adenines and cytosines.
2. By reinforcing bacterial DNA structure with covalent phosphodiester bonds.
3. By adding histones to protect the double-stranded DNA.
4. By forming "sticky ends" of bacterial DNA to prevent the enzyme from attaching.
DNA fragments separated by gel electrophoresis are shown. Mark the correct statement:
1. Band 3 contains more positively charged DNA molecules than bond 1.
2. Band 3 indicates more charge density than bands 1 and 2.
3. Band 1 has longer DNA fragment than bands 2 and 3.
4. All bands have equal length and charges but differ in base composition.
Consider the characters of a scientific technique:
I. It amplifies the gene of interest
II. It is a vital part of molecular diagnosis of diseases
III. It relies on thermal cycling
The technique is
1. ELISA
2. Southern Blot
3. PCR
4. PAGE
Consider the following characters of an application of biotechnology:
I. It is seen in all eukaryotes as a mechanism of self defense
II. It involves silencing of an mRNA due to a ds RNA
III. Fire and Mello got a noble prize for discovering this technique
This technique is used in:
1. Gene therapy for some genetic diseases
2. Developing transgenic models for human diseases
3. Developing piggyback vaccines
4. Developing pest resistant plants
Which of the following have the ability to replicate within bacterial cells independent of the control of chromosomal DNA?
1. Plastids and plasmids
2. Plasmids and bacteriophages
3. Plastids and mitochondria
4. Plasmids, plastids, bacteriophages and mitochondria