Question 1

Which of the following statements about plasmids is INCORRECT?

Accepted Answer

They usually carry essential genes for bacterial survival.

Question 2

During prophase I of meiosis, what is the primary function of the synaptonemal complex?

Accepted Answer

To hold homologous chromosomes together and facilitate crossing over.

Question 3

Which process is responsible for the direct transfer of DNA from one bacterium to another via a physical connection?

Accepted Answer

Conjugation

Question 4

A bacterium that cannot synthesize a required nutrient and cannot grow on minimal medium is called a(n):

Accepted Answer

Auxotroph

Question 5

Which of the following best describes horizontal gene transfer?

Accepted Answer

Transfer of genetic material between unrelated organisms, not involving reproduction.

Question 6

In the interrupted mating technique, genes that are transferred earlier are:

Accepted Answer

Closer to the origin of transfer on the chromosome.

Question 7

If two loci cotransform frequently during bacterial transformation, what does this indicate?

Accepted Answer

They are closely linked on the chromosome.

Question 8

Which of the following is a key difference between the lytic and lysogenic cycles of bacteriophages?

Accepted Answer

The lysogenic cycle involves integration of viral DNA into the host genome, while the lytic cycle results in host cell lysis.

Question 9

Which type of E. coli cell contains the F factor integrated into its chromosome and is capable of high-frequency gene transfer?

Accepted Answer

Hfr cell

Question 10

A partial diploid (merozygote) in bacteria is formed when:

Accepted Answer

An F' plasmid carrying bacterial genes is transferred to an F− cell.

Question 11

Which of the following is NOT an advantage of using bacteria for genetic studies?

Accepted Answer

They have large, complex genomes.

Question 12

Which equation best represents the relationship between cotransduction frequency ($$f) $$and the distance ($$d) $$between two genes?

Accepted Answer

$$f \propto \frac{1}{d}$$

Question 13

In Davis’s U-tube experiment, what result indicated that direct cell-to-cell contact is required for bacterial conjugation?

Accepted Answer

No prototrophic recombinants were observed when a filter separated the two strains.

Question 14

Which of the following statements about gene transfer in bacteria is TRUE?

Accepted Answer

Transformation involves uptake of free DNA from the environment.

Question 15

A bacteriophage accidentally packages a piece of host DNA and transfers it to another bacterium. This process is called:

Accepted Answer

Transduction

Question 16

Which of the following best explains why genes closer together on a bacterial chromosome are more likely to be cotransformed?

Accepted Answer

They are more likely to be present on the same DNA fragment taken up during transformation.

Question 17

Which of the following cell types results from the conjugation of an F+ cell with an F− cell?

Accepted Answer

Two F+ cells

Question 18

Which of the following is a real-world application of bacterial plasmids in biotechnology?

Accepted Answer

Production of human insulin using recombinant DNA technology.

Question 19

Which of the following statements about the F factor in E. coli is correct?

Accepted Answer

The F factor can exist as a plasmid or integrate into the bacterial chromosome.

Question 20

Which of the following best describes the outcome of an Hfr × F− conjugation?

Accepted Answer

The recipient remains F− but may acquire new chromosomal genes.

Genetic Mapping and Gene Transfer in Prokaryotes: Study Notes

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