1. Topics Common ancestor (green algal charophyte)
Plant Kingdom
Ch. 27 & 28
Topics
Common ancestor (green algal charophyte)
Adaptations to terrestrial life
Plant life cycles
Four major plant groups – cladograms
Ecology and economy

2. Plants ~445 mya (Paleozoic era), plants colonized land
Seedless Plants
Ch. 27. pp
Plants
~445 mya (Paleozoic era), plants colonized land
> 300,000 spp.
Across the Earth
Complex, mostly autotrophic, multicellular organisms, small to huge (duckweeds to sequoias)
Green algae (ancestors) and plants share
Chlorophyll a and b, carotenoids
Starch and cellulose
Cell plate during cell division
Alternation of generation
Molecular homology

3. More complex and variable alternation of generation
Seedless Plants
Ch. 27. pp
Major Adaptations
More complex and variable alternation of generation
Gametophyte
Antheredia - sperms
Archegonia - an egg
Embryophytes
Sporophyte
Sporogenous
cells - spores

4. Plant Evolution Issue of desiccation in dry atmosphere - cuticle and
Seedless Plants
Ch. 27. pp
Plant Evolution
Issue of desiccation in dry atmosphere - cuticle and
stomata, embryo protected by archegonia, roots,
vascular tissue, lignin

5. Bryophytes - Nonvascular Plants
Seedless Plants
Ch. 27. pp
Bryophytes - Nonvascular Plants
Most closely related to green algal ancestor (charophyte)
Spores found in 460 million year-old sediments
>15,000 species
Typically small, require damp regions - no vascular system, roots, stems, leaves
Three groups:
Liverworts (Phylum, Hepaticophyta - thalloid/leafy)
Mosses (Phylum, Bryophyta - leafy)
Hornworts (Phylum, Anthocerotophyta - thalloid)

6. Mosses: Phylum - Bryophyta. ~ 9,000 spp., importance of rain/standing
Seedless Plants
Ch. 27. pp
Mosses: Phylum - Bryophyta. ~ 9,000 spp., importance of rain/standing
water to complete life cycle – many male-female separate

7. Seedless Vascular Plants
Kingdom – Plantae
Ch. 27. p
Seedless Vascular Plants
Club ‘mosses’ (Lycopodiophyta) and Ferns (Pteridophyta) – two clades
Vascular tissue - large size - strength - lignin
Earliest vascular plants ~420 mya –
sporophytic dominance

8. Kingdom – Plantae
Ch. 27. p
Pteridophyta

9. Pteridophyta - Life Cycle
Kingdom – Plantae
Ch. 27. p. 573.
Pteridophyta - Life Cycle

10. Seed Plants Topics Seeds Gymnosperms: Naked Seeded Plants
Kingdom – Plantae
Ch. 28, p
Seed Plants
Topics
Seeds
Gymnosperms: Naked Seeded Plants
Cycads - Cycadophyta
Ginkgo biloba - Ginkgophyta
Conifers – Coniferophyta (Pinophyta)
Gnetophytes - Gnetophyta
Angiosperms: Flowering Plants – Anthophyta (Magnoliophyta)
Flower – Two major classes
Monocots – Class, Monocotyledones (Liliopsida)
Dicots – Class, Eudicotyledones (Magnoliopsida)
Adaptations of flowering plants

11. Seed Develops from Consists of Fertilized ovule
Kingdom – Plantae
Ch. 28, p
Seed
Develops from
Fertilized ovule
(Ovule = Megasporangium covered by integument)
Consists of
Embryonic sporophyte
Nutritive tissue
Protective coat

12. Seeds - Reproductively Superior
Kingdom – Plantae
Ch. 28, p
Seeds - Reproductively Superior
Development - more derived than spore
Embryo is a tiny plant
Spore is merely a haploid cell
Contains food supply
Allows development and growth until the new plant can establish local nutritive support
Covered by a tough seed coat
Protection, extended dormant period
Seeds covered in ovary (fruit) or not – Gymnosperms
and angiosperms
Draw the cladogram of seed plants

13. Gymnosperms Angiosperms Seeds Exposed on cone Within fruit
Kingdom – Plantae
Ch. 28, p
Gymnosperms Angiosperms
Seeds
Exposed on cone
Within fruit
Growth
Woody tree/shrub
Woody/herbaceous
Repr. structure
Cone (usually)
Flower
Pollen dispersal
Wind
Animals or wind
Fertilization
Egg + sperm zygote
Double fertilization in gnetophytes
Egg + sperm zygote
2 polar nuclei + sperm
endosperm
Double fertilization
Xylem & phloem
Fewer cell types
More cell types & more efficient transport
No. of species
~840
>300,000
Distribution
Worldwide

14. Gymnosperms – largest bodies
Kingdom – Plantae
Ch. 28, p
Gymnosperms – largest bodies
Cycadophyta
Dioecious

15. Ginkgophyta Only one species, G. biloba native to China - dioecious
Kingdom – Plantae
Ch. 28, p
Ginkgophyta
Only one species, G. biloba native to China - dioecious
Oldest genus of living trees; 200 million year old fossils - look identical to modern ginkgoes
Pollution-tolerant, popular urban tree
Popular medicinal

16. Coniferophyta 630 species: pines, spruces, hemlocks, firs etc.
Kingdom – Plantae
Ch. 28, p
Coniferophyta
630 species: pines, spruces, hemlocks, firs etc.
Mainly monecious: male, female structures in same plant
Strobili (cones) - reproductive structures
Woody trees and shrubs - clear annual growth rings
No herbaceous spp.
Many conifers - make resin
Sticky, protect plant from attack by insects and fungi

17. Conifers - usually
evergreen, some deciduous
- bald cypress and
redwoods
Kingdom – Plantae
Ch. 28, p
Gnetophyta
Vessel elements, cone clusters like flower clusters, and some broad-leaved plants - like Anthophytes – but likely not in the same evolutionary lineage.

18. Flowering Plants - Anthophyta
Kingdom – Plantae
Ch. 28, p
Flowering Plants - Anthophyta
>300,000 species - dominant plants on Earth - economic benefits
From small herbaceous plants to huge trees
Flowers - conspicuous or cryptic
Sexual reproductive structure - flower - double fertilization produces seeds within fruits
Vessel elements in xylem; sieve tubes in phloem
(more efficient water/nutrient, and sugar conduction)

19. Kingdom – Plantae
Ch. 28, p
A complete flower

20. Feature Eudicots Monocots Seed Embryo with 2 cotyledons
Kingdom – Plantae
Ch. 28, p. 586.
Feature
Eudicots
Monocots
Seed
Embryo with 2 cotyledons
Embryo with 1 cotyledon
Flower parts
In fours/fives
In threes
Leaf venation
Netted
Parallel
Vascular bundles in stem
Arranged in ring
Scattered or complex
Roots
Taproot system
Fibrous roots
Secondary growth (wood, bark)
Often present
Absent

21. Kingdom – Plantae
Ch. 28, p. 589.

22. Adaptations of Flowering Plants
Kingdom – Plantae
Ch. 28, p
Adaptations of Flowering Plants
Seed - protection + dispersal
Closed carpels (fruit) aid in dispersal (animal dispersal too)
Flowers attract pollinators
Pollen - well-adapted to cross-fertilization via pollinators
Double fertilization – increases reproductive success
Improved water and sugar transport in xylem and phloem
Broad leaves, well-developed roots - absorb and store nutrients
Cacti, Trees, Lilies, Vines, Shrubs - Sporophytic adaptations critical to success