Biology, Eighth Edition (Raven)

Chapter 28: Prokaryotes

Bacterial Conjugation - Transfer of a Plasmid

Is bacterial conjugation the same as sex in eukaryotes? Conjugation is commonly referred to as the bacterial equivalent of sex. Conjugation is equivalent to sex in that it combines genetic material from two different individuals into a single genome. Like sexual reproduction conjugation produces new genetic combinations. Sexual reproduction is tied to the production of new individuals. Sex involves the vertical transfer of genes, genetic information is passed down (vertically) from parents to offspring. Conjugation is not involved in reproduction, as no new individuals are produced. Conjugation is an example of the lateral transfer of genes.

View the animation below, then complete the quiz to test your knowledge of the concept.


1.	Which of the following does NOT occur during bacterial conjugation?

		A)	direct contact between donor and recipient cells
		B)	shortening of the pilus
		C)	enzymatic cleavage of one strand at the origin of transfer
		D)	unidirectional transfer of both DNA strands
		E)	recipient cell becomes a donor cell after conjugation

2.	During bacterial conjugation, plasmid replication occurs in

		A)	the donor only.
		B)	the recipient only.
		C)	both the donor and recipient.
		D)	either the donor or the recipient, but not both.
		E)	neither the donor nor the recipient.

3.	If one donor cell is mixed with 20 recipient cells, eventually ________ cells will become donors.

		A)	2
		B)	5
		C)	10
		D)	15
		E)	20

4.	The pilus is found on both the donor and recipient cells.

		A)	True
		B)	False

5.	Plasmids are small pieces of DNA that may carry genetic information for antibiotic resistance.

		A)	True
		B)	False