Plants ppt

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The Venus Flytrap
The Kingdom Plantae
Kingdom Plantae
Recall:
DOMAIN
Eukarya
KINGDOM
Plantae
EXAMPLE
Maple Tree
CELL TYPE
Eukaryote
NUMBER OF CELLS
Multicellular
CELL WALL MATERIAL
Cellulose
NUTRITION
Autotrophs
PRIMARY MEANS OF
REPRODUCTION
Sexual
How Plants Evolved
Algae
Multicellular algae ("seaweed") are divided into 3 main
groups (phyla) based on their colour: brown, red, or green.
Algae are photosynthetic aquatic protists.
The only other kingdom that contains multicellular photosynthetic
members is the plant kingdom.
Some scientists say that green algae are plants, while others
consider them protists.
However, scientists do agree that plants evolved from
algae, and green algae are the evolutionary link between
the two groups.
Why is it believed that green algae are the closest
evolutionary relatives of land plants?

The earliest land plants were small, grew in moist places
and transferred water and dissolved nutrients from cell
to cell by osmosis and diffusion.
To grow successfully on land, plants developed
several adaptations including:
 the formation of an embryo, a reproductive
structure that develops into a plant
 the ability to stand upright and grow tall to get as
much sunlight as possible
 tissues to transport nutrients, waste, and water
 strategies to reduce water loss
 strategies to disperse reproductive structures without
water currents (i.e. wind/via pollinator)
3 Key Characteristics of Plants
1. Eukaryotic
2. Cells have cell walls that contain cellulose
3. Carry out photosynthesis, using the pigment
chlorophyll
Evolutionary Age of Various Plants
Fossil & biochemical evidence indicate that green algae are the oldest
group of plants and flowering plants the youngest.
The Kingdom Plantae:
Vascular vs. Non-Vascular

The suffix -phyte comes from the Greek work for "plant".

Non-Vascular Plants have NO vascular tissue (no true
roots, stems, and leaves). They must depend on the
processes of diffusion and osmosis to transport nutrients

Vascular Plants have vascular tissue to transport
materials and nutrients throughout the plant and
between its cells.
◦ E.g. Xylem and Phloem

They have true roots, stems and leaves. Allows for
plants to grow tall.
Non-Vascular Plants (Bryophytes):
3 phyla - mosses, liverworts, and hornworts
 Grow very close to the ground in damp areas where they can
obtain their water easily
 They hold water like a sponge
 Lack a rigid support

Vascular Seedless Plants:




3 phyla - ferns, club mosses, and horsetails
vascular tissue allows them to grow tall
posses rigid support structures that allow them to
stand
tall and transport water upward
The “Need” for “Seed”

Seeds allow plants to
reproduce sexually without
needing water, and provide
protection against harsh
environmental conditions.

Seeds are plant embryos
packaged in a protective
coat along with a food
supply (cotyledon).

Seeds can survive without
water for many years.
Vascular Seed Plants Gymnosperms:



conifers (eg. pine, spruce, cedar trees)
cone-bearing trees (coniferous trees)
seeds are exposed on the surface of cones and not
protected by an ovary ("naked seeds")
Vascular Seed Plants Angiosperms:

aka. flowering plants

diverse types - non-coniferous trees (eg. oak,
maple, birch), wheat, grasses, weeds, roses and
trilliums.

flowers functions as reproductive and seed
dispersal structures

"angiosperm" means "enclosed seed“

upon pollination, the ovary often develops into a
fruit
◦ fruit - the ripened ovary of a flower
Flowers - specialized structures
for sexual reproduction
Homework
Read pages 90-104
 #1-3 (p. 93), 7, 9, 12 (p.97), 13, 15 (p.101)
 #1, 5, 6, 10, 12 (p.104)

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