Green Plants

Answers to Activities

Layer	Description	Function
waxy cuticle	waterproof layer of wax which makes the leaf shiny	prevents moulds growing on the leaf surface and water vapour from escaping
upper epidermis	thin, flat cells	protective upper layer
palisade layer	tall thin cells, tightly packed with a lot of chloroplasts which make the upper surface of the leaf dark green	most photosynthesis takes place here
spongy layer	rounded cells with air space in between and few chloroplasts	oxygen and carbon dioxide can diffuse through the air spaces
lower epidermis	thin, flat cells and guard cells surrounding stomata (pores)	allows oxygen and carbon dioxide to diffuse in and out of the leaf