Competent cells are defined as which?

Competent cells are defined as which?

• A. Cells that have thick cell walls
• B. Cells that are resistant to transformation
• C. Cells that are actively dividing
• D. Cells that have the ability to take in DNA from the environment

Answer: (D)

Competence is the ability of a cell to take up DNA from its environment. This property is what allows transformation to occur, as the cell can import extracellular DNA and potentially incorporate it or maintain it as plasmid DNA. In experiments, cells are made competent so plasmid DNA can cross the membrane and enter the cell. The other statements don’t define competence: a thick cell wall isn’t the defining feature of DNA uptake; being resistant to transformation is the opposite of being competent; and active division isn’t a requirement for DNA entry, since competence centers on the cell’s ability to take up DNA, not its growth state. Some bacteria are naturally competent, while others are rendered competent by chemical or electrical methods to enable DNA entry.

Competence is the ability of a cell to take up DNA from its environment. This property is what allows transformation to occur, as the cell can import extracellular DNA and potentially incorporate it or maintain it as plasmid DNA. In experiments, cells are made competent so plasmid DNA can cross the membrane and enter the cell. The other statements don’t define competence: a thick cell wall isn’t the defining feature of DNA uptake; being resistant to transformation is the opposite of being competent; and active division isn’t a requirement for DNA entry, since competence centers on the cell’s ability to take up DNA, not its growth state. Some bacteria are naturally competent, while others are rendered competent by chemical or electrical methods to enable DNA entry.