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Three Basic Organ in Plant
Reproductive shoot (flower)
• Three basic organs
evolved: roots,
stems, and leaves
• They are organized
into a root
system and a shoot
system
Terminal bud
Node
Internode
Terminal
bud
Shoot
system
Vegetative
shoot
Leaf
Blade
Petiole
Axillary
bud
Stem
Taproot
Lateral roots
Figure 35.2
Root
system
The Three Basic Plant Organs:
Roots, Stems, and Leaves
• The basic morphology of vascular
plants
– Reflects their evolutionary history as
terrestrial organisms that draw
nutrients from two very different
environments: below-ground and
above-ground
Roots
• A root
– Is an organ that anchors the vascular
plant
– Absorbs minerals and water
– Often stores organic nutrients
AKAR / ROOTS
• Fungsi Akar
• Perkembangan Akar
• Tipe – Tipe akar
• Modifikasi Akar
• Simbiosis di akar
http://w3.dwm.ks.edu.tw/bio/activelearner/35/images/ch35summary.gif
Fungsi Akar
• Attachment to substrate (ground,
etc)
• Water and nutrien uptake
• Transport
In several plants:
• Food storage
• Oxygen uptake
• Climber
• In most plants
– The absorption of
water and
minerals occurs
near the root tips,
where vast
numbers of tiny
root hairs increase
the surface area of
the root
Figure 35.3
Perkembangan akar
Primary Growth of Roots
Cortex
• The root tip is covered
by a root cap, which
protects the delicate
apical meristem as the
root pushes through
soil during primary
growth
• The primary growth of
roots
– Produces the
epidermis, ground
tissue, and vascular
tissue
Epidermis
Key
Root hair
Dermal
Zone of
maturation
Ground
Vascular
Zone of
elongation
Apical
meristem
Root cap
Figure 35.12
Vascular cylinder
100 m
Zone of cell
division
• Lateral roots
Arise from within
the pericycle, the
outermost cell
layer in the
vascular cylinder
100 m
Emerging
lateral
root
Cortex
Vascular
cylinder
1
2
Epidermis
Lateral root
Figure 35.14
3
4
Sistem Perakaran
Tipe Akar Berdasarkan
Pembentukannya
• Akar Tunggang
• Akar Serabut
• Akar Adventif (lainnya)
Tipe – Tipe Akar
Akar papan/banir
Akar tunjang
• Many plants
have modified
roots
(a) Prop roots
Figure 35.4a–e
(d) Buttress roots
(b) Storage roots
(c) “Strangling” aerial
roots
(e) Pneumatophores