MCQOPTIONS
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MCQOPTIONS
This section includes 39 Mcqs, each offering curated multiple-choice questions to sharpen your Cytogenetics knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
5’ |GAAGTTCCTATGC||CGAAGTTCCTATTC||TCTAGAAA||GTATAGGAACTTC 3’ 3’ CTTCAAGGATACG||GCTTCAAGGATAAG||AGATCTTT||CATATCCTTGAAG 5’ If the DNA segments are named a, b, c and d respectively; and d is in opposite orientation to a and b, which of the following is dispensable for recombianse action? |
| A. | a |
| B. | b |
| C. | c |
| D. | d |
| Answer» B. b | |
| 2. |
Excision of the lamda phage genome from bacterial genome requires IHF and _______________ |
| A. | Integrase from phage and XIS from bacteria |
| B. | FIS from phage and XIS from bacteria |
| C. | FIS from phage and INT from bacteria |
| D. | XIS from phage and FIS from bacteria |
| Answer» E. | |
| 3. |
Integration of the phage into bacterial genome requires__________________ |
| A. | Integrase and XIS |
| B. | Integrase and IHF |
| C. | XIS and IHF |
| D. | XIS and FIS |
| Answer» C. XIS and IHF | |
| 4. |
If there is a flanking region between two similarly oriented LoxP sequence, what will be its fate on site-specific recombination? |
| A. | It will remain as it is |
| B. | It will be inserted |
| C. | It will be excised out |
| D. | The regions surrounding it will be exchanged |
| Answer» D. The regions surrounding it will be exchanged | |
| 5. |
How many mechanisms are involved in the recombination process? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» D. 4 | |
| 6. |
What is the nature of the DNA complex formed by the recombination process? |
| A. | Hydrophilic |
| B. | Hydrophobic |
| C. | Amphipathic |
| D. | Non polar |
| Answer» C. Amphipathic | |
| 7. |
What is the correct pair of the four segments (R1, R2, R3, and R4)? |
| A. | R2 and R3, R1 and R4 |
| B. | R2 and R1, R3 and R4 |
| C. | R1 and R2, R3 and R4 |
| D. | R1 and R3, R2 and R4 |
| Answer» B. R2 and R1, R3 and R4 | |
| 8. |
Which recombinases cleaves the four strands before strand exchange occurs? |
| A. | Serine |
| B. | Threonine |
| C. | Alanine |
| D. | Arginine |
| Answer» B. Threonine | |
| 9. |
What are the two proteins which create site specific recombination? |
| A. | DNA topoisomerases and Spo11 |
| B. | DNA gyrase |
| C. | DNA ligase |
| D. | DNA helicase |
| Answer» B. DNA gyrase | |
| 10. |
How many classes of sequences are carried by the recombination site? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» C. 3 | |
| 11. |
INTEGRATION_OF_THE_PHAGE_INTO_BACTERIAL_GENOME_REQUIRES__________________?$ |
| A. | Integrase and XIS |
| B. | Integrase and IHF |
| C. | XIS and IHF |
| D. | XIS and FIS |
| Answer» C. XIS and IHF | |
| 12. |
WHAT_IS_THE_CORRECT_PAIR_OF_THE_FOUR_SEGMENTS_(R1,_R2,_R3,_AND_R4)??$ |
| A. | R2 and R3, R1 and R4 |
| B. | R2 and R1, R3 and R4 |
| C. | R1 and R2, R3 and R4 |
| D. | R1 and R3, R2 and R4 |
| Answer» B. R2 and R1, R3 and R4 | |
| 13. |
IF_THERE_IS_A_FLANKING_REGION_BETWEEN_TWO_SIMILARLY_ORIENTED_LOXP_SEQUENCE,_WHAT_WILL_BE_ITS_FATE_ON_SITE-SPECIFIC_RECOMBINATION??$ |
| A. | It will remain as it is |
| B. | It will be inserted |
| C. | It will be excised out |
| D. | The regions surrounding it will be exchanged |
| Answer» D. The regions surrounding it will be exchanged | |
| 14. |
5’ |GAAGTTCCTATGC||CGAAGTTCCTATTC||TCTAGAAA||GTATAGGAACTTC 3’$# |
| A. | |
| B. | |
| Answer» B. | |
| 15. |
How many mechanisms are involved in recombination process?$ |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» D. 4 | |
| 16. |
Excision of the lamda phage genome from bacterial genome requires IHF and _______________$ |
| A. | Integrase from phage and XIS from bacteria |
| B. | FIS from phage and XIS from bacteria |
| C. | FIS from phage and INT from bacteria |
| D. | XIS from phage and FIS from bacteria |
| Answer» E. | |
| 17. |
What_is_the_nature_of_the_DNA_complex_formed_by_the_recombination_process?$ |
| A. | Hydrophilic |
| B. | Hydrophobic |
| C. | Amphipathic |
| D. | Non polar |
| Answer» C. Amphipathic | |
| 18. |
What is the function of Salmonella Hix invertase? |
| A. | Inversion of chromosomal region |
| B. | Promotion of DNA deletion |
| C. | Promotion of DNA integration |
| D. | Promotion of base inversion |
| Answer» B. Promotion of DNA deletion | |
| 19. |
In mice you place are protein under an inducible promoter and you insert the gene under study in the loxP flanking region between opposite segments. If this tissue is induced which of the following will you see? |
| A. | There will be no visible result |
| B. | The gene under study will be deleted from specific induced cell |
| C. | The gene under study will be deleted from all other than the induced cell |
| D. | The gene will be inserted in the Cre gene sequence |
| Answer» C. The gene under study will be deleted from all other than the induced cell | |
| 20. |
What is the name of the site where Cre enzyme acts? |
| A. | COX |
| B. | LOX |
| C. | AOX |
| D. | XOP |
| Answer» C. AOX | |
| 21. |
Site specific recombination is not used in__________________ |
| A. | Life cycle for lamda phage |
| B. | Expression of specific genes during specific stage of development |
| C. | Promotion of programmed DNA rearrangements in embryonic development |
| D. | Recombination repair |
| Answer» E. | |
| 22. |
What is the enzyme involved in the tyrosine recombination process? |
| A. | Cre recombinase |
| B. | DNA polymerase |
| C. | Transcriptase |
| D. | DNA recombinase |
| Answer» B. DNA polymerase | |
| 23. |
Which of the following is wrong? |
| A. | Site specific recombination between two linear chromosomes result in exchange of segment |
| B. | Site specific recombination between two circular chromosomes will result in insertion |
| C. | Site specific mutation in one linear molecule will lead to excision |
| D. | For recombination to take place recombinase is a must |
| Answer» D. For recombination to take place recombinase is a must | |
| 24. |
How does tyrosine recombinase acts? |
| A. | First join then cleave |
| B. | First cleave then join |
| C. | Both process occur simultaneously |
| D. | Cleaves and rejoin two DNA pairs one after another |
| Answer» E. | |
| 25. |
Which recombinases cleaves the four strands before strand exchange occur? |
| A. | Serine |
| B. | Threonine |
| C. | Alanine |
| D. | Arginine |
| Answer» B. Threonine | |
| 26. |
Which of the following is an example of site specific recombination? |
| A. | Conjugation in bacteria |
| B. | Lysogeny in lambda phage |
| C. | Transformation in bacteria |
| D. | Lytic cycle in phage |
| Answer» C. Transformation in bacteria | |
| 27. |
How many single strands are generated during recombination? |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» E. | |
| 28. |
If there is 8 bp sequence flanking oppositely oriented 13bp symmetry elements like LoxP, what will be the fate of it after recombination? |
| A. | It will be excised out |
| B. | It will be inverted |
| C. | It will be broken in the middle |
| D. | It will be inserted in another region |
| Answer» C. It will be broken in the middle | |
| 29. |
What are the two proteins which creates site specific recombination? |
| A. | DNA topoisomerases and Spo11 |
| B. | DNA gyrase |
| C. | DNA ligase |
| D. | DNA helicase |
| Answer» B. DNA gyrase | |
| 30. |
Which one of these is a cis factor in site specific recombination? |
| A. | Cre |
| B. | Int |
| C. | LoxP |
| D. | Flp |
| Answer» D. Flp | |
| 31. |
Site specific recombination is ATP dependent process. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 32. |
Site-specific recombination can be called an economic process. State whether it is true or false. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 33. |
What are the two families of conservative site specific recombinases? |
| A. | Alanine and phenylalanine |
| B. | Threonine and valine |
| C. | Arginine and lysine |
| D. | Serine and tyrosine |
| Answer» E. | |
| 34. |
In recombinase the activated ______________ residue performs the catalytic attack. |
| A. | Serine |
| B. | Threonine |
| C. | Tyrosine |
| D. | Cystine |
| Answer» C. Tyrosine | |
| 35. |
In recombinase recognition sequences what is the short sequence? |
| A. | Crossover region |
| B. | Cleavage region |
| C. | Restriction region |
| D. | Attachment region |
| Answer» B. Cleavage region | |
| 36. |
Site specific reaction between two circular plasmids could result in__________________ |
| A. | A single circular chromosome |
| B. | Two recombinant circular chromosomes |
| C. | One recombinant linear chromosome and another circular |
| D. | Two recombinant linear chromosomes |
| Answer» B. Two recombinant circular chromosomes | |
| 37. |
CSSSR can generate ____________ Different types of DNA rearrangement. |
| A. | 1 |
| B. | 2 |
| C. | 3 |
| D. | 4 |
| Answer» D. 4 | |
| 38. |
Which of the following is a must for site-specific recombination reaction? |
| A. | Resolvase |
| B. | Ligase |
| C. | Rejuvinase |
| D. | Recombinase |
| Answer» E. | |
| 39. |
What is the level of sequence homology required for site specific recombination? |
| A. | Only homologous chromosomes participate |
| B. | A homologous stretch of 3-5 kb |
| C. | A homologous stretch of 20-200bp |
| D. | No sequence homology necessary |
| Answer» D. No sequence homology necessary | |