algae, bryopytes, pteridophytes, gymnosperms and angiosperms
TRANSCRIPT
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