Download PLANT STRUCTURE GL

PLANT
STRUCTURE
EQ: How can a plant maintain homeostasis
using its stomata?
Basic Morphology
Stem
Leaves
3 Organs?
Roots
Roots?
Anchor
Absorb minerals and water
Store food
Fibrous root systems
Anchors / + Surface Area
No one root is larger than the others
Taproot system
Anchor / Store Food
One long, thick root with smaller
branch roots
Root hairs
Absorption of water and minerals
Increase the surface area enormously
Shoots
Stems and Leaves
Stem Functions:
1. Hold up leaves to sun
2. Transport substances within the plant
3. Produce leaves, branches, flowers
Primary Growth =
growth in length of
stem occurring at the
ends of a plant
Secondary Growth =
growth in the thickness
of stem and root to
support the mass of
primary growth
Leaves
main photosynthetic organs
Blade = thin, flattened part,
maximize light absorption
Petiole = connects the leaf to
a stem node
Transpiration and Wilting
Transpiration = loss of water through leaves. Helps to
cool leaves on hot days but also can threaten leaf’s
survival if water is limited.
Anatomy of a Leaf
Cuticle
Blade
Epidermis
Veins
Xylem
Petiole
Palisade
mesophyll
Vein
Mesophyll
Spongy
mesophyll
Chloroplasts
Phloem
Stoma
Gases out: O2, H2O
Gases in: CO2
Gas Exchange and Homeostasis
Stomata (singlular: stoma) = small openings in the epidermis
that allow gases (CO2, O2, H2O) to diffuse into and out of the
leaf.
Guard Cells = surround the stomata, control opening and closing.
Leaves have become adapted by evolution for other functions
tendrils to cling to supports
modified for water storage
spines for defense
brightly colored for
attracting pollinators