PLANTS
CHARACTERISTICS OF PLANTS
Cell wall containing
cellulose
 Carry out photosynthesis
using chlorophyll
 Most autotrophic; some are
parasites or saprobes
 Sessile (can’t move)

PLANT NEEDS:


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Sunlight- to carry out photosynthesis
Gas Exchange- plant requires oxygen for
cellular respiration & carbon dioxide to carry
out photosynthesis
Water & minerals- from the soil
PLANT LIFE CYCLE

Consists of two alternate generations :

Gametophyte multi-cellular haploid organism that
produces gametes by mitosis (either male or female)


Fusion of gametes  zygote that grows into a sporophyte
Sporophyte multi-cellular diploid organism that produces
spores by meiosis; spores germinate and grow into
gametophytes
VASCULARIZATION
 Tube-like
elongated cells through which
food and other materials are transported
Xylem: transports water & minerals from the
roots
 Phloem: transports sugar from leaves to
other parts
 Roots: absorb water and minerals from the
soil; anchors the plan to the ground
 Stem: provides support for growth
 Leaves: flat organ that traps light

CHARACTERISTICS OF PLANTS
 Divided
into 4 groups- based on embryo
formation, specialized water conducting
tissues, seeds and flowers
Bryophytes
 Pteridophytes
 Gymnosperms
 Angiosperms

SEEDLESS PLANTS (NON-VASCULARIZED)

Bryophytes (Bryo means moss; phyte means plant)
Mosses & Liverworts- attachment on a moss are not roots;
they don’t absorb water and minerals like true roots
 Don’t contain true vascular system (can’t support tall plant)

SEEDLESS PLANTS (VASCULARIZED)

Pteridophytes (Pteris means fern; phyte means
plant)

Examples: ferns, horsetails, club mosses & whisk ferns
The leaves (fronds) have a lacy appearance
 Found where there is a fair amount of moisture; needs
moistures so spores can move for reproduction

Fern
Whisk Fern
Horsetail
SEED PLANTS

Gymnosperms- bear seeds in cones (evergreens/conifers)
Gymnosperm means “plant with naked seeds”
 Examples include: cycads, fir trees, fir, pine trees, cypress,
spruce, ginkgo and redwoods

SEED PLANTS

Gymnosperm seeds are inside the cones:
Pollen cones- male cones produce pollen grains; male
gametophyte
 Seed cones- female cones; female gametophytes

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Cycle occurs in the spring male cone releases pollen; female
cone captures the grains
SEED PLANTS
Angiosperms- bear seeds in flowers
 “Angio” means container; “sperm” means seed
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Flower contains ovaries that surround and protect the seeds
After pollen reaches ovaries, ovaries develop into fruits
(surround, protects & disperse the seeds)