CHAPTER 5 BACTERIAL TRANSFORMATION & POLYMERASE CHAIN REACTION

1. What is the clinical significance of Bacterial transformation in biotechnology?

antibiotic resistance spread enables genetic engineering for insulin production, and underlies gene therapy vectors.

2. When did Griffith discover transformation?

1928

3. How did the mouse die in station 1?

from pneumonia in a live s-strain virus

4. what did the s-strain contain

polysaccharide capsule

5. How was the R-strain different from the s-strain?

lacks a capsule

6. What happened in station-3 of griffith's experiment?

mouse survives— dead bacteria cannot replicate

7. What happened in station 4?

heat-killed s strains and a mix of r strain kills the mouse

8. How did the bacteria demonstrate genetic variation?

r strain aquiredcirulene from dead s strain dna

9. What happens during DNA release and uptake in the transformation process?

s chromosome/dna segment released from heat killed bacteria contains capsule synthesis gene

10. What happens during DNA integration?

nucleases degrade one dna strand while complementary strand integrates via homologous recombination

11. What happens during Bacterial division in the transformation process?

dividing bacterium replicates hybrid chromosome containing S strain capsule gene

12. What is the clinical significance of Bacterial conjugation?

bacterial transformation explains horizontal gene transfer mechanisms responsible for rapid antibiotic resistance dissermination, enables recombinant dna technology for pharmaceutical production, and provides insights into genetic engineering approaches for human gene therapy

13. What are the different bacterial mating types?

F+ bacterium

F+ chromosome

F- bacterium

F- chromosome

fertility factor

14. What is the Fertility Factor?

episomal dna conferring donor ability

15. What is the conjugation bridge?

Pilus encoded by F factory genes creates bridge bbetween cells

16. How are genes transferred during conjugation?

through the plasmid

17. What is high frequency Recombination?

18. What is Bacterial Transduction?

enables bacteriophages to transfer genetic material between bacteria

19. What happens during Bacteriophage attachment?

bacteriophage recognized specific receptor sites on bacterial surface

20. What happens during phage DNA replication?

DNA segments compromises fragmented bacterial chromosomal DNA

21. What happens during packaging and phage release?

Abberant packaging occurs when bacterial DNA segments mistakenly packaged

22. What are the steps of generalized transduction?

23. What happens during prophage integration and excision?

Donar bacteria harbors integrated prophage DNA within chromosome

24. What is hybrid DNA Formation?

contains partial phage genome fused with specific bacterial genes

25. How is DNA transferred to recipient?

receives hybrid dna through phage infections

26.What is the pre-integration state?

host bact contains recipient chromosome prior to integration

27. What is the post-integration State?

homologous recombination integrates donor dna into host chromosome

28. What is the clinical significance of Bacterial Transduction?

mediates virulence factor transfer in staph and strep

29. How did genetic engineering revolutionize medicine?

enabling bacteria to produce human proteins like insulin, growth hormones, and blood clot-dissolving enzymes

30.What is the donor plasmid

small circular dna molecule isolated from e coli bact.

31. What are restriction enzymes

molecular scissors

what are dna ligases

molecular glue

where do foreign dna come from

other bact. animal tissue, human cells

what is a chimera

recombinant plasmid created from foreign dna

what does CaCl2 solution do to cells

opens cell walls and membranes, permits chimera entry

how does the host bacteria reproduce quickly

through binary fission

how can recominant proteins be used

gain accsess to human insulin

how did pcr revoltutionize medicine

enabled rapid testing

what are primers

specific binding sites

what are dnTPs

building blocks for new dna synthesis

what is taq dna polymeraase

synthesizes new dna strands

what are the three steps of pcr

denaturization annealling and elongation

what temp does denaturation happen

95

what happens during the denaturation phase

separates bonds

whst temp does nnealing happen

50-65

what happens during annealing phase

primers bind to template

what temp does elongation happen at

72

what occurs during elongation stage

synthesizes new dna strands

how does pcr multiply

2^n

how many cycles of pcr are typical

30