BIODIVERSITY

Power point@lecture Slides Are Prepared By Biology Lecturer, KMPk

11.5 KINGDO

M PLANTAE

11.5.3 GMNOSPERM11.5.4 ANGIOSPERM

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OBJECTIVESAt the end of this lecture, students should be able to:

• Describe the unique characteristics of Gymnosperms

• State the classification of Gymnosperms into 4 phyla:

Phylum Coniferophyta (Pinus sp.) Phylum Cycadophyta (Cycas sp.) Phylum Ginkgophyta (Ginkgo sp.) Phylum Gnetophyta (Gnetum sp.)

OBJECTIVES• Describe the unique characteristics of

Angiosperms (Phylum Anthophyta/Magnoliophyta)

• State the classification of Gymnosperms into 2 classes:

Class Dicotyledonae (Hibiscus rosa-sinensis)

Class Monocotyledonae (Zea mays)

11.5.3 GYMNOSPERMS

11.5.3 GYMNOSPERMS

•“Naked seed”-Seeds are exposed on the surface of

spore producing structures-Sporophylls

Unique Characteristics

•Reproductive organs are usually

borne in cones -Sporophylls are spirally arranged

•Non flowering plant

•Ovules (modified megasporangium) -Contain the female gametophyte

Unique Characteristics

• Vascular cambium leads to secondary growth (wood)

• Have vascular tissues

-Xylemo Tracheids only

-PhloemoNo companion cells

• Sporophyte dominant

• Gametophyte very much reduced-Depends entirely on the

sporophyte

-No free living gametophyte

• Heterosporous-Microspores

-Megaspores

Classified into 4 phyla:• Coniferophyta (Pinus sp.)• Cycadophyta

(Cycas sp.)• Ginkgophyta (Gingko biloba)• Gnetophyta

(Gnetum sp.)

Gingko

Phylum Coniferophyta-Pinus sp.

Male cone Female cone

PHYLUM CYCADOPHYTACycas sp.

PHYLUM CYCADOPHYTACycas sp.

Male sporophylls Female sporophylls

Phylum Ginkgophyta-Gingko sp.

Phylum gnetophyta-Gnetum sp.

11.5.4 ANGIOSPERMS

11.5.4 ANGIOSPERMS

• Vascular, seed plants– Seeds enclosed in fruit

• Flowering plants– Produce flowers and fruits

Unique Characteristics

• Herbaceous and woody plant• The most diverse and geographically widespread

Unique Characteristics

• Vascular tissues– Xylem• Tracheids• Vessels : in most species• Fiber cells : support• Efficient water transport

– Phloem• Sieve tubes • Companion cells

• Alternation of generation– Sporophyte is dominant• The plant body

– Gametophyte is very much reduced• Male gametophyte– Pollen grains

• Female gametophyte– Embryo sac

• Reproduction involves double fertilization

Classification• PHYLUM :

ANTHOPHYTA/MAGNOLIOPHYTA• Can be divided into 2:– Class Monocotyledonae• Seed has 1 cotyledon• Eg: Zea mays

– Class Dicotyledonae• Seed has 2 cotyledons• Eg: Hibiscus rosa-sinensis

• Eg: Zea mays• Leaves– Narrow– Parallel veins

• Stems– Vascular bundles scattered– No vascular cambium– Usually herbaceous or soft-wooded

CLASS MONOCOTYLEDONAE

• Roots– Adventitious with

many branches

• Flower– Petals patterns are in

multiples of three

• Eg: Hibiscus rosa-sinensis• Leaves– Broad– Branched or netted veins

• Stem– Vascular bundles arranged in ring– Herbaceous or woody– Woody plants have vascular cambium

CLASS DICOTYLEDONAE

• Roots – Taproot • A single large root that grows deep underneath the plant

• Flower– Petals patterns are multiples of four

or five

Evolutionary relationship among groups in the plant kingdom

BRYOPHYTA PTERIDOPHYTA

GYMNOSPERMS

ANGIOSPERMS

Size Very small Medium Large Large

Dominant generation

Gametophyte Sporophyte Sporophyte Sporophyte

Dependence of gametophytes and sporophytes

Sporophyte depends on the gametophyte for the rest of its life

Sporophyte depends on the sporophyte only at the early development

Sporophyte is totally independent

Sporophyte is totally independent

Water dependence in fertilization

Needed Needed Not needed Not needed

Vascular tissues

Absent Simple vascular tissues

PresentXylem – tracheids onlyPhloem – Sieve tubes with no companion cells

PresentXylem – tracheids and vesselsPhloem- Sieve tubes and companion cells

Embryo protection

Not protected Not protected Protected by the seed

Protected by the seed

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KINGDOM ANIMALIA