Transcript Practical 3: general anatomy of the leaf

Variation in leaf anatomy
SPECIMENS:
1. Ligustrum TS
2. Pinus TS
3. Nerium oleander leaf TS
4. Amaranthus. TS
5. Nymphaea TS
6. Zea mays TS
(+)
Ligustrum
palisade
xylem
this leaf is
bifacial
fascicular cambium
phloem
spongy mesophyll
(-)
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©CEJB’99
Adaxial epidermis
palisade
xylem
phloem
Spongy mesophyll
stoma
Ligustrum
Pine needle
epidermis
stoma
hypodermis
transfusion tissue
mesophyll
endodermis
Transfusion tissue
resin canal
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transfusion tissue
protoxylem
metaxylem
secondary xylem tracheids
fascicular cambium
secondary phloem
primary phloem
endodermis
transfusion tissue
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Nerium oleander
minor vein
Stomatal crypt
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CO2 /O2
exchange
Amaranthus (pigweed) grows in disturbed farmland.
Grown as ornamental ground cover. This is a C4 dicot.
(+)
Kranz mesophyll
Bundle sheath cells
©CEJB’99
(-)
Guard cell (stoma)
(+)
KMS
BS
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(-)
bulliform cell
adaxial
Kranz mesophyll
MX
MX
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abaxial
stoma
Bundle sheath
Zea mays is a C4 grass. So like Amaranthus, the vascular bundles are surrounded
by a BUNDLE SHEATH and exarch to this, the KRANZ MESOPHYLL
TS Zea mays, vascular bundle
protoxylem
Bundle sheath
metaxylem
phloem
epidermis
©CEJB’99
(+)
Nymphaea
sclerieds
Intercellular
air spaces
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(-)
And so, we come to
the end of this short
talk, time to move on
and think of larger
things that stand with
their feet in the
ground and have
Little green bits
sticking out up the
stalk..
Redwood, Yosemite California
©CEJB’76