Post on 29-Nov-2014
description
(multicellular green plants and advanced algae)
Further divided into 5 divisions
• Division 1 – Thallophyta
(Gr., thallus – plant body without root, stem & leaves, phyton - a plant) Algae
e.g. – Ulothrix, Cladomonas, Ulva, Chara, Spirogyra
Ulothrix Spirogyra
Cladomonas Ulva Chara
• Division 2 – Bryophyta
( Gr., bryon – a moss, a liverwort)
e.g. - Riccia, Marchantia, Funaria
Riccia Marchantia
Funaria
• Division 3 – Pteridophta
( Gr., pteris, - idos – fern)
e.g. – Selaginella, Lycopodium, Marsilea, Equisetum, Azolla, Adiantum, Dryopteris
Selaginella
Lycopodium
Marsilea Equisetum
Azolla Adiantum Dryopteris
• Division 4 – Gymnosperm
(Gr. Gymno – naked, sperma –seed)
e.g. – Cycus, Pinus, Ginkgo
Cycus
Pinus
Ginkgo
• Division 5 - Angiosperm
(Gr., angeion – case ; Sperma - seed)
• Sub Division I – Monocotyledon
( mono – one, cotyledon – seed leaf)
e.g. – Maize, Wheat, rice, onion, sugarcane, barley, banana, coconut
Wheat Rice Sugarcane
• Sub Division II – Dicotyledon ( di – two; cotyledon – seed leaf)
e.g. – Pea, potato, sunflower, rose, banyan, neem, apple
potato
sunflower
banyan
apple
1. Division – Thallophyta
• Most primitive & simple plants. Plant body is not differentiated into stem,root and leaves but it is in the form of an undivided thallus.
• Most are aquatic – marine/ fresh water. Some are terrestrial (live on land near moist places)
• Usually contain green pigment (chlorophyll) for photosynthesis. Some algae have other photosynthetic pigments such as red, brown, blue green and purple)
• Autotrophic
• cellulose cell wall around cell• Vascular tissue absent• Reproduction – Asexual- generally by spores• Sex organs simple, single celled, no embryo
formation• Green algae - Ulothrix, Cladophora, Spirogyra,
Ulva, Chara• Red algae – Batra, Polysiphonia• Brown algae – Laminaria, Fucus, Sargassum
2. Division – Bryophyta
• multicellular, small, simplest land plants confined to shady damp places
• Plant body - flat, green thallus in liverworts & leafy, erect structures in mosses
• lack true roots, stem and leaves and have no flower
• True vascular system absent
• Gamatophyte is attached to substratum by means of hair-like outgrowths - Rhizoids
• Sex organs multicellular, embryo formed after fertilization
e.g. – liverworts – Riccia, Marchantia
mosses – Funaria, SphagnumRiccia Funaria
3. Division – Pteriodophyta
• Found in shady & damp places• plant body is made of root, stem and leaves• Vascular system – well developed • have no flowers & do not produce seeds• sex organs – multicellula & jacketed by sterile
cells, fertilized egg develops into embryo• e.g. Selaginella, Lycopodium, Equisetum,
Marsilea, Azolla, Adiantum, Dryopteris, Pteris, Pteridium
4. Division – Gymnosperm • Most primitive & simple seed plants
• seeds are naked & not enclosed within fruits
• usually perennial, evergreen and woody plants
• e.g. – Cycus, Pinus (pine) , Cedrus (deodar) , Ginkgo
CycusPinus
Ginkgo
5. Division – Angiosperm
• Highly evolved plants
• Seeds are enclosed within fruit
• Reproductive organs are aggregated in a flower
• Embryo in seeds have structures called ‘ cotyledon’ – (seed leaves)
On basis of the number of cotyledons angiosperms are divide
in 2 groupsDivision Angiosperm
Subdivision Monocoteledon Dicotyledon
Seeds Have one cotyledon Have two coteledon
Root system
Fibrous Tap
Stem Hollow (bamboo), Strong stem
Reduced to disc
( onion, garlic),
False stem (banana)
Vascular bundle
Scattered, closed (lack cambium), secondary growth does not occur
Arranged in ring, open (have cambium), undergo secondary division
Leaf Radical (arises directly from soil), sessile (without petiole), parallel venation (e.g. banana)
Petiolate (have petiole), dorsi-ventral (having dissimilar dorsal & ventral surfaces), reticulate venation (e.g. hibiscus)
flower Trimerous (parts arranged in groups of three)
Pentamerous (parts arranged in groups of five)
Examples Maize, Wheat, Rice, Onion, Sugarcane, Barley, Banana, Coconut, grasses
Pea, potato, sunflower, rose, banyan, neem, apple