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Vascular plant anatomy and growth. Biol 121, Fall 2010, Tom Buckley. 29 Sep 10. Leaves. petiole. leaf : has axillary bud leaflet : no bud compound leaf: multiple leaflets one axillary bud. leaf leaflet. Axil. Fig 35.6. Leaves. Fig 35.18. Typical leaf anatomy. adaxial surface.
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Vascular plant anatomy and growth Biol 121, Fall 2010, Tom Buckley 29 Sep 10
Leaves petiole leaf: hasaxillary bud leaflet: no bud compound leaf: multiple leaflets one axillary bud leaf leaflet Axil Fig 35.6
Fig 35.18 Typical leaf anatomy adaxial surface cuticle epidermis mesophyll palisade spongy vein bundle sheath stomata guard cells abaxial surface
Leaf anatomy fluorescence lignin: blue chlorophyll: red Karaba et al 2007 PNAS 104:15270 image by Gregory Johnson, ASU
Leaf anatomy leaf scars & bundle traces
Modified leaves tendrils (climbing) spines succulent (water storage) bracts (look like petals)
Modified stems rhizomes stolons bulbs tubers
Modified roots pneumatophores buttress roots pneumato- = air pherein = to carry
Meristems apical meristems in... apical buds axillary buds root apices Fig 35.11
bud scale scars (from apical buds) year's growth leaf scars
Meristems lateral meristems vascular cambium cork cambium Fig 35.11
Primary growth vascular bundle fascicular cambium phloem xylem fasci- = bundle
Primary growth vascular bundle X xylem P phloem
interfascicular cambium Secondary growth vascular bundle fascicular cambium phloem xylem
vascular cambium interfascicular cambium Secondary growth vascular bundle Year 1 fascicular cambium phloem xylem Year 2
Fig 35.20 late early wood wood P X { Fig 35.19 Growth ring
primary growth primary xylem and phloem secondary xylem and phloem secondary growth (woody plants only)
(Angiosperms) Dicot stem Monocot stem no secondary growth Fig 35.17
Circle dance Whirling dervishes vascular cambium
Secondary growth vascular cambium cork cambium cork
bark periderm cork cambium cork phloem { Fig 35.19
What is missing? Fig 35.23
Root growth stele (vascular cylinder) endodermis phloemxylem Fig 35.14 stele = star (e.g., 'stellar')
Q: Which term applies to the lateral meristems indicated by the arrows? (a) xylem (b) cambium (c) cork (d) cortex
Q: What is the feature surrounded by the red line? (a) leaflet (b) leaf
Q: Which is typically closer to the adaxial surface -- xylem or phloem? Q: Which is closer to the vascular cambium during winter: earlywood or latewood? Q: True or False: A leaf is a flattened structure specialised for carrying out photosynthesis. Q: How many years of growth are shown between the arrows?