Below that is the spongy mesophyll, which have plenty of space in between them for reactants to move through.

下面是海绵状中叶，它们之间有足够的空间供反应物移动通过。

Above the palisade mesophyll and below the spongy mesophyll are epidermis cells, which produce a waxy coating called the cuticle.

掌状中叶以上和海绵状中叶以下是表皮细胞，它们会产生一种称为角质层的蜡质涂层。

So the carbon dioxide comes in through the stomata, makes it's way through gaps in the airy layer of cells (called spongy mesophyll) at the bottom part of the leaf, then heads up to the palisade layer for photosynthesis.

因此，二氧化碳通过气孔进入，通过叶片底部通风层细胞（称为海绵状叶肉）的间隙，然后到达栅栏层进行光合作用。