Plant Structure and Function
Warm-up
• Which system in humans is
responsible for producing offspring
and giving birth?
• Which body system is responsible
for the transport of nutrients and
oxygen throughout the body?
Plant Body
•
•
•
Shoot system =
leaves + stem
Root system
Meristem = cells
that divide for life
of plant, can give
rise to all plant
structures
Three Types of Plant Tissues
• Vascular Tissue
– Transport
– Support
• Ground Tissue
– Synthesis of Sugars
– Storage
– Support
• Dermal Tissue
– Protection
Division of Meristem Cells
Causes Plant Growth
• Apical Meristem
– tips of root and
shoot
– increase in height
• Lateral Meristem
– cylinders within
plant body
– increase in width
Plant Body
Leaf = blade + petiole
Functions
Exposes surface to sunlight
Major site of photosynthesis
Conserves water
Provides for gas exchange
Blade
Petiole
Stoma =
opening in the leaf
for gas exchange,
water evaporation
Conserves water
Photosynthesis
Structures of the Leaf
Transports water
and sugar to stem
and roots
Plant Body
Stem: series of nodes and internodes
Functions
Holds leaves up to light
Transports substances
through vascular tissue
Xylem conducts water
and minerals
Phloem transports
sugar
Lateral Meristem Causes
the Stem to Grow in Width
Wood and Bark are
Products of Lateral Meristem
Plant Body
Root
Functions
Anchors plant in soil
Takes up water and
minerals from soil
Flowering Plant
Reproduction
• Flowers are
modified leaves,
specialized for
reproduction.
• Flower parts
undergo meiosis to
produce haploid
products
– pollen grain
– ovule (contains egg cell)
Flower
Mitosis
Meiosis
Mitosis
Pollen
grains
Ovule
A Complete Flower Has Both Produces pollen
Male and Female Parts
Pistil
Stamen
Male part
Anther
Filament
Attracts
pollinator
Stigma
Petal
Style
Sepal
Ovary
Female part
Produces egg
Encloses and
Protects Bud
Mature Pollen
Grain
Sperm Cells
Tube Cell Nucleus
2. pollen tubes grow
down stigma to ovary
Sperm
1. pollen grains
land on stigma
Stigma
Style
3B: Fusion of 2nd
sperm + two
polar nuclei
3. double
fertilization
3A: Fusion of
sperm + egg
Ovule
Polar nuclei
Ovary
Egg
Pollination
and
Fertilization
in a Flower
Development of Fruit and Seeds
From Flower Parts
Provides nutrition
Endosperm
Triploid
Endosperm
Cell Fresh
Fruit
Ovary
Seed
Integument
Coat
Diploid
Embryo
Zygote
(new
plant)
Seed = embryo + stored food + seed coat
Fruit = ovary wall, mechanism for seed dispersal
Activity
Label the parts of the flower. Then look
up and define each one.