What would happen to the rate of photosynthesis if the epidermis are very thick?

If the epidermis of a plant is very thick, it may impede the rate of photosynthesis by reducing the amount of light that penetrates to the chlorophyll-containing cells beneath. This thickness can also hinder gas exchange, restricting the uptake of carbon dioxide and the release of oxygen. Consequently, both light availability and gas exchange are essential for optimal photosynthesis, and a very thick epidermis could limit the plant's overall photosynthetic efficiency.