PLANTS

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KINGDOM PLANTAE
Grade 7
BIOLOGY
Mr. Anderson
KINGDOM PLANTAE
CHARACTERISTICS
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Eukaryotic
Autotrophic
Multicellular
Cell walls made of
cellulose
EX: ferns, mosses,
flowering plants, pine
trees
Non-examples: algae!
Taxonomy
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Plants are divided
into two groups
Based on the
presence or
absence of an
internal transport
system for water
and dissolved
materials
Called Vascular
System
Vascular
Bundles
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3
Plant Classification
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Non-vascular
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No vascular tissue (xylem
& phloem)
Reproduce with spores
instead of seeds
Need water to get sperm to
egg
Reproduction: Alternation
of generations
Live in moist, shady
environments
No roots, stems, leaves
Ex: bryophytes (moss),
liverworts
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Vascular
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Have vascular tissue
(xylem & phloem)
Can be seeded or seedless
Vascular System
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Xylem tissue carries water and
minerals upward from the roots
Phloem tissue carries sugars made
by photosynthesis from the leaves
to where they will be stored or
used
Sap is the fluid carried inside the
xylem or phloem
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Nonvascular Plants
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Do not have
vascular tissue
for support or
conduction of
materials
Called
Bryophytes
Require a
constantly moist
environment
Sporophyte stage
Gametophyte
Stage
Moss Gametophytes &
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Sporophytes
6
Nonvascular Plants
Plants can’t grow as tall
 Cells must be in direct contact
with moisture
 Materials move by diffusion
cell-to-cell
 Sperm must swim to egg
through water droplets
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Nonvascular Plants
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Includes mosses (Bryophyta),
liverworts (Hepatophyta), and
hornworts (Antherophyta)
Liverworts
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Hornworts
8
Main Parts of Vascular
Plants
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Shoots
-Found above ground
-Have leaves attached
- Photosynthetic part of
plant
Roots
-Found below ground
-Absorb water & minerals
-Anchor the plant
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Vascular Plants
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Also called
Tracheophytes
Subdivided into
two groups -Seedless
vascular plants
and Seedbearing vascular
plants
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Club Moss
10
Seedless Vascular Plants
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Includes club moss (Lycophyta),
horsetails (Sphenophyta), whisk
ferns (Psilophyta), and ferns
(Pterophyta)
Whisk ferns
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Horsetails
11
Seed-Producing Vascular
Plants
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Includes two groups –
Gymnosperms and Angiosperms
Gymnosperms have naked seeds in
cones
Angiosperms have flowers that
produce seeds to attract
pollinators and produce seeds
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Gymnosperms
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Coniferophyta are
known as conifers
Includes pine,
cedar, spruce, and
fir
Cycadophyta –
cycads
Ginkgophyta ginkgo
Cycad
Ginkgo
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Gymnosperms
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Contains the oldest
living plant – Bristle
cone pine (about
4700 years old)
Contains the tallest
living plant –
Sequoia or redwood
(379 feet tall – 30
foot diameter and
110 foot
circumfrance)
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Angiosperms
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Flowering plants
Seeds are formed when an
egg or ovule is fertilized by
pollen in the ovary
Ovary is within a flower
Flower contains the male
(stamen) and/or female
(ovaries) parts of the plant
Fruits are frequently
produced from these
ripened ovaries (help
disperse seeds)
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Angiosperms
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Division Anthophyta
Subdivided into two groups –
Monocots and Dicots
Monocots have a single seed
cotyledon
Dicots have two seed cotyledons
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Monocots
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Parallel
venation in
leaves
Flower parts in
multiples of 3
Vascular tissue
scattered in
cross section
of stem
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Dicots
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Net venation in
leaves
Flower parts in
multiples of 4
or 5
Vascular tissue
in rings in
cross section
of stem
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Plant Uses
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Why We Can’t do Without
Plants!
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Produce oxygen for the
atmosphere
Produce lumber for building
Provide homes and food for many
organisms
Prevent erosion
Used for food
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More Reasons We Can’t do
Without Plants!
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Produce wood pulp for paper
products
Source of many medicines
Ornamental and shade for yards
Fibers such as cotton for fabric
Dyes
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PLANT ANATOMY
Plant Anatomy
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ROOTS
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Anchor plant in ground
Absorb water & nutrients
Sometimes store food for
the plant (potatoes or
carrots)
Types:
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Fibrous- long hair like
fibers (grass)
Tap- one thick main root
(carrot)
Adventitious- roots grow
from stem or other plant
part (strawberry plant)
Plant Anatomy
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STEMS
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Support growth above
ground
Contain Xylem & Phloem
(vascular bundle)
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Xylem carries water up to
leaves
Phloem carries sugar down
to roots
Types
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Tubers- enlarged stem
underground (potato)
Bulbs- enlarged stem
underground that can be
divided into smaller bulbs
(garlic, onions)
Plant Anatomy
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LEAVES
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Site of photosynthesis
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CO2 + H2O + light= C6 H12 O6 + O2
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Types:
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Simple- one leaf blade
Compound- several leaf blades
attached to same stem
Tendrils- used for climbing
(vines)
Spines/Needles- small surface
area to reduce water loss in
desert or cold climate (taiga)
Pitcher shape/Venus fly trapcaptures bugs to get nitrogen so
they can make amino acids and
proteins
Thick- thick & fleshy to store
water
Leaf Shapes & Margins
(may be used in dichotomous key)
Leaf Anatomy
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Waxy cuticle- made of lipids, prevents water loss, protection
Epidermis- upper & lower surface for protection (like skin)
Palisade layer- oval shaped cells on upper surface; site of most photosynthesis
Spongy layer- has many canals to allow O2 & CO2 to circulate
Vascular bundle- holds xylem (water pipe) and phloem (glucose pipe)
 Xylem carries water to leaf for photosynthesis
 Phloem carries glucose made by photosynthesis to other parts of plant.
Stomata- openings in leaf that let O2 & CO2 in and out
Guard cells- control opening/closing of stomata. (filled w/water they open stomata)
Review of Photosynthesis
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CO2 is brought in thru stomata,
water is brought in from rootsmeet at chloroplast in palisade
layer of leaf
Sunlight splits water into
hydrogen, oxygen, and electrons
Several hydrogens, oxygens,
and CO2 combine to form
glucose C6H12O6 which is linked
together and stored as starch in
plants & used for energy
Some of the oxygen is released
as gas thru stomata
Plant Anatomy
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FLOWERS
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Used in sexual reproduction
Reproductive organ of plant
Types:
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Complete- have all parts (see
next slide)
Incomplete- missing 1 or more
parts
Perfect- have both male &
female parts
Imperfect- either male or female
Some flowers are colorful or
smell good to attract pollinators
Those that are not colorful,
showy, or smelly may use wind
as a pollinator.
Wind pollinated
flower
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Flower
Anatomy
Petals- colored part attracts pollinator
Sepals- surround & protect petals before
blooming
Pedicel- where flower attaches to stem.
Pistil- female parts
 Stigma- sticky to catch pollen
 Style- tube connecting stigma to ovary
 Ovary- holds ovules (potential seeds);
becomes fruit
 Ovules- will become seeds if fertilized
Stamen- male parts
 Anther- makes & stores pollen
 Filament- connects anther to flower;
pushes pollen close to sticky stigma
(self fertilization) or pollinators
Plant Anatomy
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SEEDS
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Produced after pollination
Become newborn plant
Types: (method of dispersal)
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Inside fruit- attracts animals to eat
& poop out seeds elsewhere
Hitchhikers- attach to fur or
clothing for dispersal
Wind- able to float in air
Water- able to float in water
Seeds need to be dispersed so they
don’t compete with parent plant
for water, nutrients, sunlight
Seeds are good adaptations for
land plants b/c
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Retain moisture
Protect from injury or environment
(cold)
Seed Anatomy
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Seed coat- protects seed
from dehydration and
weather
Cotyledon/endosperminternal starch storage
(food source b/c it doesn’t
have leaves yet for
photosynthesis)
Radicle- becomes first root
Hypocotyl- becomes first
stem
Epicotyl- becomes first
Plant Anatomy
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FRUITS
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The ripened ovary of plant
containing seeds
Protect seeds
Attracts animals for seed
dispersal
Anything that contains
seeds is a fruit- yes, even
tomatoes & bell peppers!
Types:
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Dry- bean pod
Fleshy- juicy like peach,
apple
REPRODUCTION
SEXUAL REPRODUCTION IN
MOST PLANTS
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Self-pollination: pollen fertilizes
ovules of its own flower.
Cross-pollination: pollen
fertilizes ovules of a different
flower on separate plant
Pollen holds “sperm”
Pollen creates pollen tube that
“eats” its way thru style to ovary
Plant sperm can travel down tube
to ovary to fertilize ovules and
make seeds.
Flower petals fall off, ovary
thickens & fills with sugars and
becomes fruit (not all plants make
fruits- some just release seeds)
Alternation of Generations
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Plant alternates between a
sexual and asexual stage
of life
Gametophyte (haploid)makes sperm or egg that
join to make sporophyte
Sporophyte (diploid)makes spores that become
gametophytes
EX: mosses, ferns
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ASEXUAL
REPRODUCTION IN
MOST
PLANTS
Vegetative propagation
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New plants form from roots,
stems, or leaves
Natural process for many
species
Ex: runners, rhizomes, bulbs
Artificial propagation
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Grafting
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Cuttings
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Cut one plant and attach to
another
Cut plant and sprout roots from
stem
Tissue culture
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Grow plant tissues in culture
dish in laboratory
Like cloning
ENVIRONMENTAL
INFLUENCES
How are plants influenced by the
environment?
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Photoperiodism
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Respond to changes in light
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Ex: morning glories bloom
in morning, some desert
flowers bloom at night to
attract bats, deciduous trees
drop leaves when days
become shorter (less light)
Moisture
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Xerophytes- can survive in
dry conditions (cactus)
Hydrophytes- can survive
in wet conditions (water
lilies)
How are plants influenced by the
environment
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Tropisms- how plants
move toward (positive) or
away (negative) from a
stimulus
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gravity
Thigmotropism
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Touching a structure
Hydrotropism
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Hydrotropism
light
Gravitropism
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Thigmotropism
Phototropism
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Phototropism
water
Gravitropism
How are plants adapted to their environments?
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Tundra (cold & dry)
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Taiga (cold & dry)
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Drop leaves to prevent water loss
Rainforest (shady under canopy)
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Succulents- store water in stem or leaves
Spines- deter herbivores from eating them &
reduce surface area to reduce transpiration
(water loss from leaf)
Deciduous forest (cool, dry winters)
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Needles have waxy coating to conserve water
in winter
Thick bark to conserve heat
Desert (hot & dry)
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Small- get radiant heat that bounces off
ground
May have wooly covering to conserve heat
Fast growing/reproducing (shorter summers so
have to reproduce quickly)
Large broad leaves to catch sunlight that
filters thru canopy
Drip tips to prevent excess water & mold
Grassland (sunny, fire prone)
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Roots create a mat under soil & go on for
miles, regenerate quickly after fire
Some trees need heat from fire to open up
seed cones
INTERNAL
INFLUENCES
How are plant behaviors controlled
internally?
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Hormones- send messages
thru plant to illicit responses
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Gibberelins- stimulate growth
in stem (pushes flowers up in
air to attract pollinators)
Auxins- controls when leaf &
fruit fall off tree
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Component of Agent Orangemade leaves fall off trees so
enemy easier to see.
Ethylene gas- controls
ripening of fruit & flowers
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“one bad apple spoils the
bunch”
Fruit farmers use ethylene
blankets to absorb ethylene to
keep fruit from spoiling on way
to store
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