In a cell, the separation of DNA strands is brought about by the enzyme DNA helicase, whereas in PCR, the separation of DNA strands is due to :
1. High temperature
2. Two sets of Primers
3. Taq DNA polymerase
4. Deoxynucleotides
Identify the properties of a good vector used in rDNA technology:
(a) | It should have origin of replication supporting a high copy number |
(b) | It should have preferably more than '2' recognition sites |
(c) | The restriction sites in vector should be in the antibiotic- resistant genes |
(d) | It should have suitable marker genes |
(e) | It should be easy to isolate and purify |
Choose the most appropriate answer from the options given below:
1. (a), (c) and (e) only1. | The bacterium does not contain the specific recognition sequence |
2. | The DNA is packed with histones |
3. | The specific recognition sequences are masked with methyl groups |
4. | Restriction endonucleases cut viral DNA only |
Assertion (A): | When a particular restriction enzyme cuts strands of DNA, overhanging stretches or sticky ends are formed. |
Reason (R): | Some restriction enzymes cut the strand of DNA a little away from the centre of palindromic site. |
1. | Both (A) and (R) are True and (R) correctly explains (A). |
2. | Both (A) and (R) are True and (R) does not correctly explain (A). |
3. | (A) is True, (R) is False. |
4. | (A) is False, (R) is True. |
List I | List II | ||
(a) | Gene gun | (i) | Replacement of a faulty gene by a normal healthy gene |
(b) | Gene therapy | (ii) | Used for transfer of gene |
(c) | Gene cloning | (iii) | Total DNA in the cells of an organism |
(d) | Genome | (iv) | To obtain identical copies of a particular DNA molecule |
(a) | (b) | (c) | (d) | |
1. | (ii) | (i) | (iv) | (iii) |
2. | (i) | (iii) | (ii) | (iv) |
3. | (iv) | (i) | (iii) | (ii) |
4. | (ii) | (iii) | (iv) | (i) |