1. Horizontal gene transfer - principles
2. Transformation and transduction
3. Conjugation

1. The concepts covered here can be reviewed in your textbook, pages 231-232, and your lecture notes.

2. Review the terminology involved in horizontal gene transfer. On a piece of paper write down the definitions of the following terms:

• Donor cell
• Recipient cell
• Recombinant cell
• Recombination
• Transformation
• Transduction
• Conjugation

3. In most cases, horizontal transfer involves either a plasmid or a DNA fragment. In both cases, the foreign DNA must be transferred from the donor to the recipient cell. Once plasmids are transferred into the recipient cell, the process of horizontal transfer is usually complete. When DNA fragments are transferred, the additional step of recombination is needed. To summarize all the possible types of horizontal transfer, copy and fill in the following table. Check your table by mousing over the word ANSWER below the table.

ANSWER

4. If you feel that you have mastered the concepts on this page, you can move to the next topic of this sub-unit, which explores the transfer of DNA fragments by transformation and transduction.