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waxy water barrier

palisade layer

were most photosynthetic occurs

spongy layer

some photosynthesis occurs here as well as gas exchange

guard cell

controls stoma


carbon dioxide enters O2 and water vapor exit

air space

site of gas exchange

vascular bundle

were transport occurs


transports food made during photosynthesis from the leaves to the rest of the plants

lower epidermis


upper epidermis



transport water and nutrients from the roots to the top of the plant

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