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Leaf Structure. Why is a leaf like a sandwich?. Layers of a Leaf. upper epidermis. contains cells which secrete a waxy substance called a cuticle which prevents water loss. phyll. mesophyll. contains vascular tissue (veins) and 2 types of cells containing chloroplasts. lower epidermis.
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Layers of a Leaf upper epidermis contains cells which secrete a waxy substance called a cuticle which prevents water loss phyll mesophyll contains vascular tissue (veins) and 2 types of cells containing chloroplasts lower epidermis contains stomata, guard cells phyll -o, (G suffix) a leaf chlorophyll
cuticle Parts of a Leaf upper epidermal cells palisade cells chloro chloroplasts vascular tissue spongy cells air space lower epidermal cells cuticle stomata guard cell
Guard Cells stomata guard cell epidermal cell
palisade guard spongy mesophyll Photosynthesis occurs in chloroplasts. Chloroplasts are found in 3 types of cells.
Count the palisade cells. Most photosynthetic activity occurs in the palisade cells. Describe the structure of palisade cells. more chloroplasts than spongy mesophyll and guard cells 20! lined up at top of leaf nearer to sun vertical long, narrow
Count the palisade cells. Which alignment is better?
Gas movement and exchange occur in the mesophyll layer. CO2 CO2 CO2 O2 O2 O2 O2 O2 O2 O2 O2 CO2 O2 CO2 CO2 O2 CO2 CO2 CO2 O2 O2 CO2 CO2 O2 CO2 O2 CO2 CO2 O2 CO2 CO2 CO2 O2 CO2 CO2 O2 CO2 CO2 CO2 CO2 CO2 CO2 CO2
Sandwich:Leaf Analogy Why is a leaf like a sandwich? upper epidermal cells bread peanut butter palisade cells spongy mesophyll cells jelly bread lower epidermal cells
Complete this analogy. cuticle sandwich:leaf::baggie:______
spongy mesophyll cells upper epidermal cells vascular tissue (vein) lower epidermal cells upper epidermis lower epidermis palisade cells chloroplasts guard cells mesophyll Identify. air space stomata cuticle 4 1 5 6 7 2 8 9 10 11 3 12 13 14
Identify. 4 1 5 6 7 2 8 9 10 11 3 12 13 14
regulate opening and closing of stomata allows for movement of gases within leaf transports water, minerals, food throughout leaf, plant water vapor exits here O2 exits here noncellular waxy outer covering 3 cells containing chloroplasts exact site of photosynthesis CO2 enters and exits here loosely spaced cells Identify. 4 1 5 6 7 2 8 9 10 11 3 12 13 14