Algae, Bryopytes, Pteridophytes, Gymnosperms

and Angiosperms

PLANT KINGDOM

Artificial system of classification- only superficial characters, equal weightage to sexual and vegetative characters- Linnaeus

PLANT KINGDOM

Natural system of classification- external and internal characters- Bentham and Hooker

Phylogenetic system of classification- based on evolutionary relationships

Numrical taxonomy- using computersCytotaxonomy- cytological informationChemotaxonomy- chemical constituents

classification

PLANT KINGDOM

Chlorophyll-bearing, simple, thalloid, autotrophic, aquatic. Moist stones, soil and wood. With animals or plants.

Unicellular- chlamydomonas

Colonial= volvox

ALGAE

Filamentous- Ulothrix

Kelps

PLANT KINGDOM

Reproduction: vegetative, asexual, sexual.

vegetative- fragmentation

Sexual reproduction- isogamous, anisogamous, oogamous

ALGAE

Asexual- zoospores

PLANT KINGDOM

Importance

About half of CO2 fixation by algae

Hydrocolloids- algin, carrageen

ALGAE

As food= Laminaria, Sargassum

Agar- Gelidium, Gracilaria

SCP- chlorella, spirulina

PLANT KINGDOM

Classes: Chlorophyceae, Phaeophyceae, Rhodophyceae

Green algae

ALGAE

Unicellular, colonial, filamentous

Chlorophyll a,b- in chloroplasts

Chlorophyceae

Discoid, plate, reticulate, cup, spiral, ribb0n

PLANT KINGDOM

Class:

Storage bodies- pyrenoids

ALGAE

Vegetative, asexual and sexual reproduction

Chlamydomonas, volvox, spirogyra

Chlorophyceae

PLANT KINGDOM

Class:

Brown algae

ALGAE

marine

Simple branched to kelps ( even 100 meters

Phaeophyceae

Chlorophyll a,c, carotenoids and xanthophylls

PLANT KINGDOM

Class:

Food is stored as laminarin or mannitol

ALGAE

Algin coating over cellulosic cell wall

Body- holdfast, stipe and frond

Phaeophyceae

Vegetative, asexual and sexual

Gametes are pyreformEctocarpus, dictyota

PLANT KINGDOM

Class:

Red algae- due to phycoerythrin

ALGAE

Marine- deeper ocean to surface

Multicellular, complex

Rhodophyceae

Food is stored as floridean starch

Gametes are non-motilieGracilaria, Gelidium

PLANT KINGDOM

Includes mosses and liverworts

Amphibians of plant kingdom

BRYOPHYTES

Play a major role in plant succession

Body is thallus like, lack true roots, stem or leaves.

Plant body is haploid- called gametophyte

Male sex organ- antheridium

Female sex organ- archegonium

PLANT KINGDOM

In water- antherozoids are transported to egg

Zygote is formed- diploid

BRYOPHYTES

Produce sporophyte- dependent on gametopyte

Undergoes reduction division- spores( haploid)

Spores produce gametophyte

Fuel, packing material, succession

PLANT KINGDOM

Moist shady places.

BRYOPHYTES

Plant body is thalloid

Marchantia

Thallus is dorsiventral

Asexual reproduction- gemmae

liverworts

sexual reproduction-same or different thalli- sex organs- sporophyte

PLANT KINGDOM

Gametophyte is predominant

BRYOPHYTES

Protonema – first stag- creeping

Funaria, Sphagnum

Vegetative reproduction- fragmenation and budding

Sexual reproduction- antheridia, archaegonia

mosses

Sphorophyte is more elaborate-Foot seta and capsule

PLANT KINGDOM

For medicinal purpose and as soil bindersIncludes horsetails and ferns

First terrestrial plants to possess vascular tissues

Found in cool damp shady places

Sporophyte- true root, stem and leaves

PTERIDOPHYTES

Leaves- microphylls or macrophylls

PLANT KINGDOM

Sporophylls from compact bodies- strobili or cones

Sporophytes bear sporangia in sporophylls

Produce haploid spores- produce inconspicous gametophyte- prothallus-

PTERIDOPHYTES

PLANT KINGDOM

Antheridium and archaegonium are produced in prothallus

Zygote form sporophyte

PTERIDOPHYTES

Heterosporous- selaginella, salvinia- precursor to seed habit

homosporous

Classified into Psilopsida, Lycopsida, sphaenopsida, Pteropsida

PLANT KINGDOM

Naked seeded plants

Trees and shrubs

GYMNOSPERMS

Tallest tree- Sequoia

PLANT KINGDOM

Roots are tap root

Roots have fungal association- pinus- mycorrhiza

GYMNOSPERMS

Cycas – croralloid roots- cyanobacteria

Needle like leaves, sunken stomata, thick cuticle- conifers

PLANT KINGDOM

Heterosporous- haploid micro and mega spores

Spores are produced in sporangia in cones/strobili

GYMNOSPERMS

Male strobili- microsporophyll- pollen grain

female strobili- megasporophyll-ovule- archegonia

PLANT KINGDOM

Unlike bryophytes and pteridophytes, gametophytes have no independent existence

Pollen grains are released from microsporangium- carried by air

GYMNOSPERMS

After fertilization zygote develop into embryo and the ovules into seeds which are not covered

female strobili- megasporophyll-ovule- archegonia

PLANT KINGDOM

Monocotyledons and docotyledons

Seeds are enclosed in fruits

ANGIOSPERMS

Male sex organ- anther; female sex organ- pistil

Eight celled embryosac

PLANT KINGDOM

Double fertilization

Triple fusion

ANGIOSPERMS

Egg+ male gamete= zygote- embryo

Primary endosperm nucleus + gamete = PEN

PLANT KINGDOM

Life cycle- alternation of generations

ANGIOSPERMS