Transcript Plant DivisionsHONORS

Plant Diversity
The Evolution and
Classification of
Plants
Slide # 2
Warm-up: Answer for Each
True or False
1. All plants perform photosynthesis.
2. All plants need water and nutrients.
3. All plants reproduce using flowers.
4. All plants reproduce using seeds.
Slide # 3
PLANT CHARACTERISTICS
1. Multicellular eukaryotes
2. Photosynthetic autotrophs containing
chloroplasts.
3. Non-motile (fixed to one spot)
4. Cell walls made of cellulose
5. Respond to environment and grow by
using hormones
Slide # 4
What Plants Need to Survive
1. Sunlight
2. Gas exchange - System for
taking in CO2 and releasing O2
3. Water
4. Minerals
All are needed so that plants can
carry out photosynthesis!
Slide # 5
Cladogram of Kingdom Plantae
Gymnosperms
Angiosperms
Ferns
Moss
Flowers
Seeds
Vascular tissue
Green algae
Slide # 6
Problems with Living on Land
The ancestors of plants were multicellular green algae. They
were completely immersed in water & dissolved minerals.
To move onto land, plants had to solve these problems:
1. How to get chemical resources (water, minerals,
oxygen, and carbon dioxide) separated into air and
soil
2. How to transport resources within the plant.
3. How to keep from drying out
4. How to reproduce without water
Slide # 7
SOLUTIONS (ADAPTATIONS)
1. Leaves (CO2) and roots (H2O)
2. Develop a vascular system to transport
resources in plant
3. Have a protective layer – cuticle (waxy outer
layer) to keep from drying out
4. Specialized structures for reproduction
including spores & seeds that do not dry out
Slide # 8
Vascular Tissue
1. Vascular Tissue- hollow
tube-like cells that transports
materials throughout the plant
Xylem- transports H20 up
from roots.
Phloem- transports food
made in photosynthesis to
where it is needed in the
plant.
Xylem (water)
Phloem (food)
Slide # 9
Bryophytes - NONVASCULAR
1. Live in moist, shady areas
2. NO vascular (transport) system
3. Small size because no vascular tissue
moss
4. No true roots, stems, or leaves
5. Need water for reproduction.
6. Reproduces using spores, -asexual
cell that can grow into a new
organism.
liverworts
7. Examples: Moss, Liverworts, &
Hornworts
hornworts
Slide # 10
Ferns - Seedless Vascular Plants
1. Have vascular tissue.
2. Have true roots,
stems & leaves
3. They grow in moist,
shady habitats.
4. Have underground
stems, roots, & large
leaves called fronds.
5. Reproduce using
spores, NOT seeds.
Sori
There
are
11,000
species
of ferns.
Slide # 11
Seed Plants
ADVANTAGE: reproduction IS NOT
embryo
dependent on water:
endosperm
1. Seed contains
a. A fully developed embryo
b. Food supply for embryo
c. A water-proof seed coat to keep
from drying out
Seed coat
2. Sperm transferred in water-proof
pollen through pollination by wind or
animals.
3. Developed seed-bearing structures:
Cones & Flowers
Slide # 12
Gymnosperms- “naked seed”
1. Cycad (Sago palm),
2. Ginkgo,
3. Conifer (pine, spruce, firs, cedars, sequoias,
redwoods, junipers, yews, & cypress trees)
Sago Palm
Ginkgo
Ginkgo
Sequoia
Slide # 13
Gymnosperms-Conifers
1. Most common gymnosperms are
Conifers
2. Conifers have leaves called
needles or scales have a reduced
surface area and thick waxy coat
on the needle to reduce water loss
and prevents freezing.
Pine
Juniper
Slide # 14
Slide # 14
Conifer Reproduction
1. Male cones produce
pollen and the female
cone produces eggs and
seeds.
2. Pollen is inefficiently
transferred by the wind.
3. Once mature, the scales
on the female cone dry
out and open scattering
the seeds by the wind.
Pollen
Cone
Pollen
Seed
Cone
Slide # 15
Angiosperms- “enclosed seeds”
1. Flowering plants that
encourage direct and efficient
pollen transfer (smell, color
and offering nectar)
2. Pollinators are flying insects,
birds, and bats that transfer
pollen from flower to flower.
3. Flowers contain ovaries, which
is where eggs/seeds are
produced.
4. A fruit is the pollinated ovary
containing mature seeds.
Unusual Flowers
Oak tree flowers
Maple tree flowers
Mesquite tree flowers
Slide # 16
Two Divisions of Angiosperms:
Monocots and Dicots