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Leaf
,→Key Stage 3
| style="height:20px; width:400px; text-align:center;" |The under side of a [[leaf]] showing [[Guard Cell|guard cells]] and [[Stoma|stomata]].
|}
==Key Stage 4==
===Meaning===
[[File:LeafCrossSection.png|right|300px|thumb|A cross section of a [[leaf]].]]
A [[leaf]] is an [[organ]] in the [[Shoot System|shoot system]] of a [[plant]] that uses [[photosynthesis]] to [[Producer|produce]] food for the [[plant]].
===Adaptations for Photosynthesis===
: '''Leaves''' are usually wide and thin to provide a large area to collect sunlight.
: '''Leaves''' contain [[Cell (Biology)|cells]] with many [[chloroplast]]s for [[photosynthesis]].
: '''Leaves''' have [[air]] gaps between the [[Spongy Mesophyll Cell|spongy mesophyll cells]] to allow [[Gas Exchange in Plants|gas exchange]].
: '''Leaves''' usually have more [[Guard Cell|guard cells]] and [[Stoma|stomata]] on the underside (lower epidermis) than the top side (upper epidermis). These close when the [[leaf]] gets [[dehydrate]]d, stopping [[Carbon Dioxide|carbon dioxide]] getting into the [[leaf]] which stops them using [[water]] for [[photosynthesis]].