What type of cells primarily composes the inner layer of the retina?

The inner layer of the retina is primarily composed of nerve cells, which include various types of neurons essential for processing visual information. This layer contains photoreceptors (rods and cones) that are vital for detecting light; however, the subsequent layers—including the bipolar cells, ganglion cells, and amacrine cells—are all nerve cells that play crucial roles in transmitting and processing visual signals.

These nerve cells work together to convert light into electrical signals, which are then sent to the brain for interpretation. Their structure and organization are tailored to efficiently relay information, making nerve cells the dominant type within this layer. In contrast, the other cell types listed, such as pigment cells, muscle cells, and epithelial cells, do not primarily make up the inner layer. Pigment cells are found in the retinal pigment epithelium, muscle cells are unrelated to the retina's structure and function, and epithelial cells do not play a direct role in the processing of visual stimuli. Thus, the presence of nerve cells is essential for the retina's function in vision.