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