smak bpk penabur sukabumi grade xi – science class lectures by : agustina eka h.,s.si
TRANSCRIPT
PLANT TISSUE
SMAK BPK PENABUR SUKABUMIGRADE XI – SCIENCE CLASSLectures by : Agustina Eka H.,S.SI.
TISSUE ??the smallest basic unit of cells
a group of cells that have similar forms, composition, and function
a unit of several types of tissues that are close to each other and support certain functions
some organs which are coordinate each other and conducting certain functions
cells
tissue
organ
organism
Organ system
Meristematic & Permanent TissueA. Meristematic Tissue Apical meristem Lateral meristem Intercalary meristem
B. Permanent Tissue 1. Simple permanent tissue Parenchyma Collenchyma Sclerenchyma2. Complex permanent tissue Xylem Phloem3. Protective tissue Epidermis Cork (phellem)
Meristematic Tissue
1. have thin cellulose cell walls.
2. The meristematic cells may be
spherical,oval,polygonal or rectangular in
shape.
3. compactly arranged & do not contain any
intercellular space between them.
4. contains dense or abundant cytoplasm & a
single large nucleus.
5. contain few vacuoles or no vacuoles at all
Apical meristems
Are located at the tips of roots and in the buds of shoots
Elongate shoots and roots through primary growth
The root tip is covered by a root cap
Primary meristem
Lateral Meristem
Add thickness to woody plants through secondary growth
Secondary meristem cambium :1) Vascular cambium2) Cork cambium
Vascular cambium
Located between xylem and phloem
Vascularcambium
C X CP
C
XC
XC
PP
PCX
X PC
XX
C C
Types of cell division. An initial can divide transversely to form two cambial initials (C) or radially to form an initial and either a xylem (X) or phloem (P) cell.
(a)
Accumulation of secondary growth. Although shown here as alternately adding xylem and phloem, a cambial initial usuallyproduces much more xylem.
(b)
• An overview of primary and secondary growth
In woody plants, there are lateral meristems that add secondary
growth, increasing the girth of
roots and stems.
Apical meristemsadd primary growth,or growth in length.
Vascularcambium
Corkcambium
Lateralmeristems
Root apicalmeristems
Primary growth in stems
Epidermis
CortexPrimary phloem
Primary xylem
Pith
Secondary growth in stems
PeridermCorkcambium
CortexPrimary phloem
Secondaryphloem
Vascular cambium
Secondaryxylem
Primaryxylem
Pith
Shoot apicalmeristems(in buds)
The corkcambium addssecondarydermal tissue.
The vascularcambium addssecondaryxylem andphloem.
Intercalary meristem
• Intercalary meristem :located between mature tissues, ex : base of nodes in grass stem
• Gramineae or Poaceae(rice, corn, sugar cane)
Epidermis
• Outer layer • Tightly cell • Function : to protect the
underlying cell• Modification : hair, spine,
trichome, stomata, lenticell, root hair, cuticule
Epidermis – stoma, trichomes, & root hairs
http://www.ucd.ie/botany/Steer/hair/roothairs.html
Periderm – cork & parenchyma
TWIG WITH LENTICELS
Parenchyma
• Large cell, thin wall, large vacuolesTypes :1 ) aerenchyma : aquatic plant2) Chlorenchyma : containing chloroplast
Parenchyma
Chollenchyma Function : supporting and strengthening tissue
• Cellulose and pectin thickening in the corner of the cell
Sclerenchyma • Function : organ support• Inactive cell• Cellulose and lignin thickening
Sclereids :Hard and rigidStem cortex, leaf
venetin, root, fruit, and seed
Fiber: hard elongated cells Gymnosperm woody
fiber, bark, leaf fiber, seed fiber
Sclerenchyma
Right-hand illustration modified from: Weier, Stocking & Barbour, 1974, Botany: An
Introduction to Plant Biology, 5th Ed.
SCLERIDS FIBERS
Secretory Cell
• Secrete various substances
Xylem
• Water and mineral transportation• Lignin thickeningConsists of :1) Trachea/vessel element2) Tracheid 3) Xylem fiber4) Xylem parenchyma
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings
Fig. 35.8
Phloem
• Conduction of nutrition
Consists of :1) Sieve tube2) Companion cell3) Phloem fiber4) Phloem parenchyma