Transcript Introduction to Plants

Introduction
to Plants
To Introduce
• Make a list of five
plants you might
eat during a
typical day
• Which part of the
plant are you
eating when you
eat that plant?
To Introduce
• Brainstorm a list
of products you
use that originate
from plants…….
Plants differ from Algae
• All plants are
multicellular and
develop tissues
Why are plants so
important?
Photosynthesis……..
They take in
CO2 and
Release O2.
What does this do
for us?
Characteristics of Plants
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Many celled
Most contain CHLOROPHYLL
Cell walls
Most have roots or root-like structure
Eukaryotic cells
Created to live in many different
environments
• 285,000+ species
For Review…
• Plants are beneficial because they
release carbon dioxide.
A. True
B. False
Adaptations for Land Life
1. Protection and support
• Cell walls made of CELLULOSE
• Provide structure and support
• CUTICLES are a waxy protective
layer that also keep plants from
drying out
Adaptations for Land Life
2. Reproduction
• Most land plants do not rely on
water in order to reproduce
• Two stages of reproduction:
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Sporophyte = plants make spores
Gametophytes = plants that grow
from spores
For Review…
• This provides structure and
support to a plant.
A. Cellulose
B. Cuticles
For Review…
• This structure helps a plant to not
dry out.
A. Cellulose
B. Cuticles
Classification
• Classified into major DIVISIONS
(phyla) (page 244)
• VASCULAR vs. NONVASCULAR
• Nonvascular plants do not have
special tissues to move water and
nutrients through the plant
• They rely on DIFFUSION
• Small plants
Divisions
• Seedless & Seed Plants
• Bryophyta - nonvascular plants
– Class Musci - the mosses
• Pterophyta - ferns, seedless plants
• Spenophyta – horsetails
and scouring rushes
Divisions
• Ginkgophyta – ginkgos
• Cycadophyta – cycads
• Gnetophyta – gnetums
Divisions
• Lycophyta – club mosses
• Coniferophyta - cone-forming seed
plants
• Anthophyta - fruit-forming seed plants
(Angiosperms)
– Class Monocotyledonae - plants
with one seed leaf
– Class Dicotyledonae - plants with
two seed leaves
Seedless Plants
Seedless Nonvascular
• Simple plants
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Few cells thick
No roots
No stems
No leaves
No flowers
Grow from spores
Mosses and
Liverworts
Mosses
• Simple rootless plant
with leaf-like
growths in a spiral
around a stalk
• RHIZOIDS = rootlike threads made of
a few long cells
• Osmosis
Liverworts
• “herb for the liver”
• Rhizoid made of one
cell
• Like mosses, grow in
damp areas
• WHY???
Moss Life Cycle
• Page 277 in your text book
• ALTERNATION OF
GENERATIONS =
continuous cycle which
alternates between
spore and sex cell
producing phases
• http://www.sumanasinc.com/webcon
tent/animations/content/moss.html
Moss Life Cycle
•Moss appears as soft green carpet
•GAMETOPHYTE = sex-cell producing
structure
–May produce male, female or both
–Via water male sperm splashed onto
female part and swim to eggs
• Fertilized egg develops into zygote
(diploid) that will grow into the
sporophyte
•SPOROPHYTE = spore-producing stage
–Stalk and capsule
–Capsule will release spores - haploid
–Spores germinate into threadlike
structure
Importance
• PIONEER SPECIES
– 1st to grow in new or disturbed areas
• Weathering of rocks
• Formation of soil
• Build up decaying plant materials to
provide nutrients
• Pave the way for other plants
For Review…
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A.
B.
C.
D.
The root-like threads of mosses
Hyphea
Rhizoids
Sori
Sporophyte
For Review…
• The stage in a mosses life cycle
that produces the sex-cells.
A. Gametophyte
B. Sporophyte
For Review…
• Mosses are considered a pioneer
species because
A. They ride in covered wagons
B. They grow in an area after other
species of plants begin to grow
C. They help create soil in new or
disturbed areas
Seedless Vascular
• Have vascular tissue
• Produce spores
• Tube like vascular
tissue to carry
water, minerals, and
nutrients throughout
plant
• How is this an
advantage?
• Club mosses, spike
mosses, horsetails, ferns
Club and Spike Mosses
• Produce spores at end of stems
• Lycopodium used for décor
• Resurrection Plant
Horsetails
• Jointed stem
• “scouring rush”
• Used by pioneers to scour pots and
pans (silica)
Ferns
• Largest group in Pterophyta
• Produce spores in SORI on back of
leaves
• Coal is formed from plant build up
over long period of time
• BOG = Spongy wet ground of
slowly decaying plants = Peat fuel
– Bryophytes and ferns
Fern Life Cycle
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Page 279 in your text book
RHIZOME = underground stem
FROND = leaf of a fern
SORI = spore cases
Spores released to damp soil will
germinate into heart shaped gametophyte
plants = PROTHALLUS
• This will produce sex cells to form a zygote
• Sporophyte and gametophyte can survive
on their own
Importance
• House plants
• Prevent soil erosion
• Some are edible
• Horsetails:
• Dietary supplements
• Shampoos
• Skin-care products
For Review…
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B.
C.
D.
The spore cases of a fern
Sori
Sporangia
Rhizome
Frond