Answer:

Gene Gun:
The gene gun, also known as a biolistic particle delivery system, is a device used to deliver genetic material into cells. It works by accelerating microparticles coated with the genetic material into the target cells. These microparticles act as carriers, facilitating the transfer of the genetic material into the cells.

Metal Microparticles Used in Gene Gun:
Among the different metal microparticles that can be used in gene guns, aurum (gold) is the most commonly used metal. The use of gold microparticles in gene guns has several advantages, making them the preferred choice for many researchers. Some of these advantages include:

1. Inertness: Gold microparticles are chemically inert, meaning they do not react with other substances. This property ensures that the genetic material remains stable and intact during the delivery process.

2. Biocompatibility: Gold microparticles are biocompatible, meaning they have a low level of toxicity and are well-tolerated by cells. This reduces the chances of cell damage or adverse effects on cell viability.

3. Size and Shape: Gold microparticles can be easily synthesized with a uniform size and shape, which is critical for efficient gene delivery. The size and shape of the microparticles determine their ability to penetrate the cell membrane and deliver the genetic material effectively.

4. High Density: Gold microparticles have a high density, which allows them to be accelerated to high velocities using the gene gun. This high velocity ensures efficient penetration of the target cells and facilitates the successful delivery of the genetic material.

5. Easy Detection: Gold microparticles can be easily detected and tracked within the cells using various imaging techniques. This enables researchers to monitor the delivery process and assess the efficiency of gene transfer.

Overall, the use of gold microparticles in gene guns provides a reliable and efficient method for delivering genetic material into cells. It offers researchers a versatile tool for studying gene function, gene therapy, and other applications in molecular biology and biotechnology.