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PLANT KINGDOM

By:

Dr.Ghasoun M.ali Wadai

What Is a Plant?

Multicellular eukaryotes that are

photosynthetic autotrophs

Cell walls made of cellulose

Store surplus carbohydrates as starch

Mostly terrestrial

Reproduction

Plants produce their gametes within

GAMETANGIA

Zygote develops into an embryo within a

jacket of protective cells

Embryophytes – a key adaptation to the

success of plants on land

ALTERNATION OF GENERATIONS

Occurs in life cycle of all plants

One generation is a multicellular haploid

condition and the next is a multicellular

diploid condition

Obstacles Plants Overcome

Absorb Minerals

Conserve Water

– Cuticle

– Stomata

– Guard Cells

Reproduce on Land

A Vascular System Enables

Plants to Thrive on Land

Most plants need a “plumbing” system

to transport water, minerals and

nutrients.

This system is known as

the VASCULAR SYSTEM.

Five Characteristics Unique to Land

Plants

Apical meristem – localized regions of active cell division in roots and shoots

Embryophtes – multicellular dependent embryos

Alternation of Generations

Walled spores produced in sporangia

Multicellular reproductive structures –antheridia and archegonia

Plant Classification

Non-flowering

Plants

Flowering

Spore-

bearingNaked

seeds

No

roots

with

roots

Mosses Ferns

Gymnosperms

1 seed-

leaf

2 seed-

leaves

Monocots Dicots

Plant Kingdom

Flowering

Plants

Non-flowering

Plants

. 3 groups

FernsMosses Gymnosperms

Non - flowering Plants

Do NOT produce flowers

A plant can be divided into 3 parts

Examples of Mosses

spores

Spore-producing capsule

.No true roots, No vascular tissues (no transport)

Characteristics of Mosses

.Simple stems & leaves

.Have rhizoids for anchorage

.Spores from capsules

(wind-dispersal)

.Damp terrestrial land

.Simplest plants

underground

stem

root

A leaf (finely

divided into

small parts)

.roots, feathery leaves & underground stems

Characteristics of Ferns

.have vascular tissues (transport & support)

.Damp & shady places

.Spore-producing organ on the underside of

leaves (reproduction)

needle-shaped leaves

Male cones

(in clusters)Female cones

(scattered)

.roots, woody stems

Characteristics of Gymnosperms

.needle-shaped leaves

.tall evergreen trees

.cones with reproductive

structures

.dry places

.vascular tissues (transport)

.naked seeds in female cones

. 2 groups

Monocotyledons Dicotyledons

Flowering

Plants

. roots, stems, leaves

. vascular tissues (transport)

. flowers, fruits (contain seeds)

Monocotyledons

Parallel veins

. one seed-leaf

Characteristics of Monocotyledons

. leaves have parallel veins

. herbaceous plants

. e.g. grass, maize

Dicotyledons

Veins in network

. two seed-leaves

Characteristics of Dicotyledons

. leaves have veins in network

. e.g. trees, sunflower, rose