Final answer:
An increased surface area of biological tissues enhances the rate of diffusion, while a thicker plasma membrane reduces it.
Step-by-step explanation:
The surface area of a biological tissue significantly affects the rate of diffusion. An increased surface area provides more space for substances to diffuse across, thus increasing the diffusion rate. On the other hand, a thicker plasma membrane offers more resistance, which reduces the diffusion rate. This is particularly important for cells because they need to exchange materials, such as oxygen, carbon dioxide, and nutrients, with their environment efficiently.
For biological tissues and cells, the surface area to volume ratio is a critical factor for diffusion. As a cell grows larger, its volume increases faster than its surface area, leading to a decreased surface area to volume ratio. This means a larger cell will have less surface area available per unit of volume for diffusion, making the process less efficient. Therefore, larger cells or animals might need adaptations, like a more complex or folded structure, to increase the surface area available for diffusion.
In summary, the rate at which materials can diffuse into a cell is influenced by the cell's surface area and the thickness of the plasma membrane. For large cells or organisms, maintaining a favorable surface area to volume ratio is critical to ensure efficient diffusion.