In genetic engineering, the antibiotic-resistance gene is used:
1. To select healthy vectors
2. As sequences from where replication starts
3. To keep the cultures free of infection
4. As selectable markers
Which of the following enzymes are used to join bits of DNA:
1. Ligase
2. Primase
3. DNA polymerase
4. Endonuclease
Identify the wrong statement with regards to restriction enzyme:
1. | They cut the strength at palindromic sites. |
2. | They are useful in genetic engineering. |
3. | Sticky ends can be joined by using DNA ligases. |
4. | Each restriction enzyme functions by inspecting the length of a DNA sequence. |
1. | Cosmids | 2. | Plasmids |
3. | Nucleus | 4. | Nucleoid |
Bacteria can protect themselves from getting infected by bacteriophages as they synthesize:
1. Methylase
2. Ligases
3. Plasmids
4. Endonucleases
‘Competence’ can be induced in a bacterium by treating them with:
1. Polyethylene glycol
2. A specific divalent cation
3. Colchicine
4. Alkaline phosphatase
Match the following enzymes with their functions:
Column-I |
Column-II |
||
(a) |
Restriction endonuclease |
(i) |
joins the DNA fragments |
(b) |
Exonuclease |
(ii) |
extends primers on genomic DNA template |
(c) |
DNA ligase |
(iii) |
cuts DNA at a specific position |
(d) |
Tag polymerase |
(iv) |
removes nucleotides from the ends of DNA |
Select the correct option from the following:
Options: | (a) | (b) | (c) | (d) |
1. | (iii) | (i) | (iv) | (ii) |
2. | (iii) | (iv) | (i) | (ii) |
3. | (iv) | (iii) | (i) | (ii) |
4. | (ii) | (iv) | (i) | (iii) |
DNA fragments are
1. Negatively charged
2. Neutral
3. Either positively or negatively charged depending on their size.
4. Positively charged.
Which of the following is not a feature of the plasmids?
1. Independent replication
2. Circular structure
3. Transferable
4. Single-stranded
The cutting of DNA at specific locations became possible with the discovery of
1. Ligases
2. Restriction enzymes
3. Probes
4. Selectable markers