What is the fine structure of cells determined by?

The fine structure of cells is best determined by electron microscopy. This technique utilizes a beam of electrons rather than light to create an image, which allows for much higher resolution and the ability to visualize structures at the nanometer scale. This level of detail is crucial for examining organelles, membrane structures, and other intricate components within cells that cannot be resolved with light microscopy methods.

Other microscopy techniques, while useful for various applications, do not achieve the same resolution. Light microscopy, for instance, is limited by the wavelength of visible light, which restricts its ability to distinguish between small cellular structures. Fluorescence microscopy enhances the visibility of specific components through fluorescent labeling but still relies on light, hence it has similar resolution limits to conventional light microscopy. Confocal microscopy offers improved clarity and depth, providing optical slicing of samples, yet its resolution also does not match the level provided by electron microscopy.