kingdom plantae grade 7 biology mr. anderson. kingdom plantae characteristics eukaryotic eukaryotic...
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KINGDOM PLANTAE CHARACTERISTICS
Eukaryotic Autotrophic Multicellular Cell walls made of
cellulose EX: ferns, mosses,
flowering plants, pine trees
Non-examples: algae!
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Taxonomy 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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Plant Classification
Non-vascular 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
Vascular Have vascular tissue
(xylem & phloem) Can be seeded or
seedless
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Vascular System 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
Do not have vascular tissue for support or conduction of materials
Called Bryophytes
Require a constantly moist environment
Moss Gametophytes & Sporophytes
Sporophyte stage
Gametophyte Stage
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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
Includes mosses (Bryophyta), liverworts (Hepatophyta), and hornworts (Antherophyta)
Liverworts Hornwortscopyright cmassengale
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Main Parts of Vascular Plants
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
Also called Tracheophytes
Subdivided into two groups -- Seedless vascular plants and Seed-bearing vascular plants
Club Mosscopyright cmassengale
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Seedless Vascular Plants
Includes club moss (Lycophyta), horsetails (Sphenophyta), whisk ferns (Psilophyta), and ferns (Pterophyta)
HorsetailsWhisk ferns copyright cmassengale
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Seed-Producing Vascular Plants
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
Coniferophyta are known as conifers
Includes pine, cedar, spruce, and fir
Cycadophyta – cycads
Ginkgophyta - ginkgo Ginkg
o
Cycad
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Gymnosperms
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) copyright cmassengale
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Angiosperms 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
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 Parallel
venation in leaves
Flower parts in multiples of 3
Vascular tissue scattered in cross section of stem
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Dicots Net venation
in leaves Flower parts
in multiples of 4 or 5
Vascular tissue in rings in cross section of stem copyright cmassengale
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Why We Can’t do Without Plants!
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!
Produce wood pulp for paper products
Source of many medicines Ornamental and shade for
yards Fibers such as cotton for
fabric Dyes copyright cmassengale
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Plant Anatomy
ROOTS Anchor plant in ground Absorb water & nutrients Sometimes store food for
the plant (potatoes or carrots)
Types: 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
STEMS Support growth above ground Contain Xylem & Phloem
(vascular bundle) Xylem carries water up to
leaves Phloem carries sugar down to
roots Types
Tubers- enlarged stem underground (potato)
Bulbs- enlarged stem underground that can be divided into smaller bulbs (garlic, onions)
Plant Anatomy
LEAVES Site of photosynthesis CO2 + H2O + light= C6 H12 O6 + O2
Types: 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 trap- captures bugs to get nitrogen so they can make amino acids and proteins
Thick- thick & fleshy to store water
Leaf Anatomy 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
CO2 is brought in thru stomata, water is brought in from roots- meet 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
FLOWERS Used in sexual reproduction Reproductive organ of plant Types:
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
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
SEEDS Produced after pollination Become newborn plant Types: (method of dispersal)
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
Retain moisture Protect from injury or environment
(cold)
Seed Anatomy
Seed coat- protects seed from dehydration and weather
Cotyledon/endosperm- internal 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 leaf
Plant Anatomy
FRUITS 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: Dry- bean pod Fleshy- juicy like peach,
apple
SEXUAL REPRODUCTION IN MOST PLANTS
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
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
ASEXUAL REPRODUCTION IN MOST PLANTS
Vegetative propagation New plants form from roots,
stems, or leaves Natural process for many species Ex: runners, rhizomes, bulbs
Artificial propagation Grafting
Cut one plant and attach to another Cuttings
Cut plant and sprout roots from stem Tissue culture
Grow plant tissues in culture dish in laboratory
Like cloning
How are plants influenced by the environment?
Photoperiodism Respond to changes in light
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 Xerophytes- can survive in
dry conditions (cactus) Hydrophytes- can survive in
wet conditions (water lilies)
How are plants influenced by the environment
Tropisms- how plants move toward (positive) or away (negative) from a stimulus Phototropism
light Gravitropism
gravity Thigmotropism
Touching a structure Hydrotropism
water
Phototropism
Gravitropism
Thigmotropism
Hydrotropism
How are plants adapted to their environments? Tundra (cold & dry)
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) Taiga (cold & dry)
Needles have waxy coating to conserve water in winter
Thick bark to conserve heat Desert (hot & dry)
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) Drop leaves to prevent water loss
Rainforest (shady under canopy) Large broad leaves to catch sunlight that filters thru
canopy Drip tips to prevent excess water & mold
Grassland (sunny, fire prone) 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
How are plant behaviors controlled internally?
Hormones- send messages thru plant to illicit responses Gibberelins- stimulate growth in
stem (pushes flowers up in air to attract pollinators)
Auxins- controls when leaf & fruit fall off tree
Component of Agent Orange- made leaves fall off trees so enemy easier to see.
Ethylene gas- controls ripening of fruit & flowers
“one bad apple spoils the bunch” Fruit farmers use ethylene blankets
to absorb ethylene to keep fruit from spoiling on way to store