Download Plant Physiology

Plant Physiology
1. Plant Parts a.k.a. Plant Organs
2. Plant Tissues
3. Water Transport
4. Food Transport
Plant Tissues
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Dermal
Vascular
Ground
Meristematic
Dermal Tissue
a.k.a. skin tissue
 outermost layer that protects the plant
 epidermis – tightly packed, one cell thick layer
– on non woody organs and young parts
 cuticle – waxy coating serves as waterproofing
 cork – protects inner tissues from injury; more than
one cell thick
Vascular Tissue
a.k.a. transport tissue
 xylem (vessel elements (only in angiosperms)
and tracheids (in all vascular plants))
 transports water and minerals
 form long continuous tubes with ends that are
absent or perforated
 dead cells reinforced with cellulose and lignin
 phloem (sieve tube cells and companion
cells)
 transports sugars
 smaller than xylem and are alive
 companion cells direct the operation of the sieve cell
Ground Tissue
a.k.a. filler tissue
 the majority of cells in plants are this type of
tissue – rather varied in function
 parenchyma cells – most of plant – provides
support, storage, photosynthetic if contain
chloroplasts; thin and flexible cell walls, large
vacuoles
 collenchyma and sclerenchyma cells –
specialized with thicker and rigid cell walls thus
provide support
 cortex – generalize cells in root and stems
Meristematic Tissue
a.k.a. growth tissue
 produces new cells by mitosis; plants only
grow where there is meristematic tissue
 apical meristem at ends of shoot and root tips;
responsible for primary growth (growth in length)
 vascular cambium in woody plants; responsible for
secondary growth (growth in width)
 cork cambium produces cork, an outer protective
layer on woody stems