LEAF STRUCTURE
B4a
THE LEAF
What might happen to leaf structure
if climate change continues?
OBJECTIVES
Key Objective
 Describe the role of specialised cells in aiding
photosynthesis
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Describe how the main features of the plant are
linked to photosynthesis (E-G)
Explain how leaves are adapted for efficient
photosynthesis (C/D)
Explain how the structure of a leaf palisade cell is
related to its function (C/D)
Identify the process by which gases travel in and out
of the plant (C/D)
Explain how the cellular structure of a leaf is adapted
for efficient photosynthesis (A/B)
PRACTICAL
Designing leaves for different environments
PLENARY
 Draw
this diagram of a Marram grass leaf.
MARRAM GRASS IS FOUND ON SAND
DUNES.
1)
2)
3)
4)
5)
6)
Add the two missing labels (D)
What does the waxy cuticle do? (C)
How does the position of the stomata
help this plant? (C)
Why are there no stomata on the outer
surface of the leaf? (B)
Explain the function of the hairs on the
inner surface of the leaves? (A)
Explain how having sunken stomata
will affect gaseous exchange in the
plant, and why this would be an
advantage to the plant. (A*)
FOR G-E:
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Identify the chloroplasts, vacuole and cell wall in a plant
cell.
State that chloroplasts absorb light energy for
photosynthesis.
State that photosynthesis occurs mainly in the leaves.
Describe the entry points of materials required for
photosynthesis:
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water through roots;
carbon dioxide through leaf pores.
Describe the exit point of materials produced in
photosynthesis:
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oxygen through leaf pores.
KEY WORDS:
 chlorophyll; cuticle; guard cell; lower epidermis; palisade
mesophyll; spongy mesophyll; stomata; upper epidermis;
vein
FOR C/D

Name and locate the parts of a leaf:
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Explain how leaves are adapted for efficient
photosynthesis:
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cuticle;
upper and lower epidermis;
palisade and spongy mesophyll layers;
stomata and guard cells;
veins.
broad so large surface area;
thin so short distance for gases to travel;
contain chlorophyll to absorb light;
have a network of veins for support and transport;
stomata for gas exchange.
State that the exchange of gases is by diffusion.
Explain how the structure of a leaf palisade cell is related
to its function:
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contains many chloroplasts.
FOR A*-B:

Explain how the cellular structure of a leaf is
adapted for efficient photosynthesis:
epidermis is transparent;
 palisade layer at the top containing most of the
chloroplasts;
 air spaces in the spongy mesophyll allow diffusion
between stomata and photosynthesising cells;
 internal surface area / volume ratio very large.
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