plant classification everything you need to know about kingdom plantae everything you need to know...
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Plant ClassificationPlant Classification
Everything You Need to Know About
Kingdom Plantae
Everything You Need to Know About
Kingdom Plantae
Characteristics
• Photosynthetic• Multicellular • Eukaryotic• Cell walls made up of cellulose• Sexual (seeds and spores) and asexual
(vegetative propagation) reproduction• Common ancestor was green algae (a
protist)
2 Categories of Plants:Vascular and Nonvascular
• Vascular tissue is specialized tissue for the transport of water and solutes through a plant
Vascular Plants• Vascular plants make up over 90% of all
plants• Ferns (seedless), gymnosperms (cone
bearing) and angiosperms (flowering plants)
• Xylem and phloem make up vascular tissue– Xylem- tissue that carries water and
minerals upward in a plant– Phloem- tissue that carries sugars (from
photosynthesis) upward and downward in a plant
Vascular Plants• Have roots
– To absorb water, anchor the plant in the ground, protect the plant from bacteria and fungi
– Two types of roots• Taproot- enlarged primary root; grows
deep below the surface (carrot)• Fibrous- numerous, extensively branched
roots, grow near the surface (prevents topsoil from being washed away (grass)
Vascular Plants
• Have stems– Holds leaves up to sunlight and
transport water and food between roots and leaves
Water Transport Food Transport
Vascular Plants
• Have leaves– Collect light for photosynthesis– Have stomas- pores in epidermis of
leaf for carbon dioxide, water vapor and oxygen to be exchanged
Stoma
Vascular Plants
• Reproduce by seeds and spores– Ferns- have spores, no seeds (sperm
and egg)– Gymnosperms- seeds in cones (pine
tree)– Angiosperms- seeds in flowers
(deciduous trees, flowers and bushes)
Seedless Vascular Plants
• Ex: Clubmoss, horsetails & ferns– Have true roots, stems, leaves & veins
Nonvascular Plants- Bryophytes
• Mosses, liverworts and hornworts• Lack vascular tissue for long
distance transport of water and solutes
• More dependent on water, need to live in moist environment
Nonvascular Plants
• Lack true roots, stems and leaves• Have rhizoids- long, thin cells that
anchor them to the ground and absorb water and minerals
• Need water for sexual reproduction– for sperm to swim to egg
Moss, liverwort & hornwort
Human Uses of Mosses
• Sphagum- a group of mosses that live in acidic water or bogs
• Acts as a natural sponge• Peat moss for fuel and shipping
products
Adaptations
• Cuticle to reduce water loss• Lignin to make cell walls harder which
allows trees to grow taller and spread branches and leaves to catch sunlight
• Bud scales to protect buds from winter temperatures
• Deciduous trees lose their leaves and become dormant in winter
Plant Life Cycle
• Alternation of Generations• Plants have two alternating phases
in their lifecycle• A diploid (2N) phase
– Sporophyte (makes spores by meiosis)
• A haploid (N) phase– Makes gametes by mitosis
Alternation of Generations
Sporophyte (2N)Gametophyte (N)
Spores (N)
MEIOSIS
FERTILIZATIONEggs (N)
Haploid
Diploid
Parts of Leaf
• Mesophyll- ground tissue where photosynthesis takes place
• Guard Cell- specialized cells in the epidermis that controls the opening and closing of the stoma
• Cuticle- waxy coating on leaf to reduce water loss• Epidermis- outer layer of the leaf• Xylem- cells that carry water upward from the
roots• Phloem- cells the transport sugars throughout the
plant• Stoma- pore-like openings in the underside
of the leaf that allow CO2 and O2 to diffuse in and out of the leaf
Parts of Leaf
A Perfect Flower• A perfect flower is one that contains both male
and female reproductive structures.• The male reproductive structures are
collectively called the stamen. • The stamen consists of the filaments and
anthers. • The female structures are collectively called
the pistil. • The pistil consists of the ovary, style and
stigma. • The sepals and the petals are called
sterile structures since they are not part of the reproductive system.
A Perfect Flower
A Perfect Flower• Sepals- usually green surrounding the flower
and protect the flower while it is developing• Petals- Often brightly colored and attracts
insects and other pollinators• Stamen- Male portion of the flower
– Anther- oval sac where pollen is made– Filament- long, thin stalk that supports the anther
• Pistil (Carpel)- Female portion of the flower– Ovary- contains ovules (female gametophyte)– Style- stalk to carpel (connects stigma to ovary)– Stigma- top sticky portion of the pistil
(carpel), where the pollen lands
Angiosperm Reproduction
Comparing Features of Seed Plants
Feature Gymnosperms Angiosperms
Seeds Bear their seeds on cones Bear their seeds within flowers
Reprod. Can reproduce without water; male gametophytes are contained in pollen grains; fertilization occurs by pollination
Can reproduce without water; male gametophytes are contained in pollen grains; fertilization occurs by pollination
Ex: Conifers, cycads, ginkgoes, gnetophytes
Grasses, flowering trees, shrubs, wildflowers, cultivated flowers
Plant Response
• Phototropism- tendency of plant to grow light.
• Gravitropism- response of a plant to the force of gravity (why plants grow up)
• Photoperiodism- response of plants to periods of light and dark
Tree Parts
• Heartwood- contains old xylem; provides tree with support.
• Sapwood- contains active xylem• Vascular Cambium- produces new
xylem• Cork Cambium- produces cork• Cork- contains nonfunctioning
phloem
Bark
Cork- contains old nonfunctioning phloem
Vascular Cambium- produces new xylemXylem: Sapwood- contains
active xylem
Phloem
Xylem:
Heartwood- contains old xylem provides the tree with support