DNA delivery by microinjection — Which statement is NOT true about microinjecting DNA into plant protoplasts?

Introduction / Context:
Microinjection is a direct physical method for introducing DNA, RNA, or proteins into individual plant cells or protoplasts. The technique requires precision instrumentation and gentle handling to avoid lysis, especially because protoplasts lack a cell wall and are osmotically fragile.

Given Data / Assumptions:

• Protoplasts are spherical, wall-less cells enclosed only by a plasma membrane.
• Micromanipulators and microcapillaries are standard equipment.
• Cells must be stabilized during injection to prevent movement and damage.

Concept / Approach:
The microinjection needle must be substantially finer than the target cell to penetrate the membrane with minimal disruption. A needle larger than the cell diameter would catastrophically damage the cell. Therefore, the statement claiming a larger-than-cell needle is used is not true.

Step-by-Step Solution:

Verification / Alternative check:
Protocols specify tip diameters in the submicron to a few microns range, far below typical protoplast diameters (20–50 microns).

Why Other Options Are Wrong:

Common Pitfalls:
Using excessive injection pressure or a too-wide tip causes lysis; osmotic stabilization and gentle manipulation are essential.

Final Answer:
It employs a needle with a diameter greater than the cell diameter.