1. Kingdom Plantae

2. The Shift to Land
Hypothesis that green algae are the closest evolutionary relatives of land plants based on
Presence of chlorophyll a and b
Cellulose cell walls
Store food in form of starch
Similarities in genetic code
However there are key differences

3. Adaptations to Life on Land
Since plants live in terrestrial environments, need protection from drying and system to transport water and nutrients
Plants only evolved from aquatic to terrestrial environments 460 million years ago
Reproduce using embryos (spores in algae)
Development of vascular tissue,
seeds and flowers

4. Vascular tissue, leaves and roots
First land plants were small and simple and did not have vascular tissue; eventually evolved to vascular plants
Vascular tissue allowed evolution of roots
Allowed anchoring
Absorb and transport water
Increased range of plants into drier environments
Leaves came next
Increased surface area of plant allowed better exchange of gases involved in photosynthesis and light capture

6. General Characteristics
Use photosynthesis to gain energy, therefore autotrophic.
Live in all aquatic and terrestrial habitats except at the poles.
Through photosynthesis plants take in carbon dioxide and provide oxygen for the environment.
Three main parts of the plant are root, stem and leaves.

7. General characteristics cont.
Roots - penetrate the soil to anchor the plant and reach sources of water
Leaves - provide a greater surface area for photosynthesis
Stem - supply rigid tissues that raise and support the leaves
Vascular tissue acts like a circulatory system and transports water, nutrients, and dissolved minerals to all parts of the plant
A seed is a structure made up of an embryo, stored food and tough waterproof coat
Life cycle consists of two generations which alternate between a haploid gametophyte and diploid sporophyte stage.

8. Classification of Plantae
Although there are a vast variety of plants (over 300,000 known species) in the world, they can all be placed in one of four main groups based on vascular tissue and seeds.
Each large group contains several divisions, which are the rough equivalent to a Phylum.

9. Classification of Plants
Bryophytes (mosses)
non-vascular, seedless
Ferns
vascular, seedless
Gymnosperms (conifers)
vascular, non-enclosed seeds
Angiosperms (flowering plants)
vascular, enclosed seeds

10. 1) Non-Vascular Plants (Mosses and their relatives)
Three divisions (mosses, hornworts and liverworts).
No vascular tissue, so depend on osmosis and diffusion to transport nutrients.
Usually grow in dense mats of low tangled vegetation that can hold water like a sponge, allowing them to survive cold or dry periods.
Have no roots, instead have root-like rhizomes which are small root like structures
Sexual reproduction.

11. Non-vascular Plants Mosses (Bryophytes)
Very successful and widespread, thrive in such diverse habitats as bogs, tundra, on bare exposed rocks, and in deep shade.
Twice as many species of mosses as there are mammals!
Sporophytes do not contain chlorophyll
Liverworts (Hepatophytes)
Grow flat, low to the ground and are rarely more than 30 cells thick.
80% are leafygametophytes that resemble mosses. Live in tropical forests and in humid climates.
20% have gametophystes with flattened, lobed bodies called thalli that resemble the lobes of animal’s livers.
Many small chloroplasts per cell.

12. Non-Vascular Plants cont.
Hornworts (Anthocerophytes)
Broad, flat
Usually blue-green in colour.
Sporophyt looks like mini-green cattle horns
One large chloroplast per cell

13. 2) Seedless Vascular Plants (Ferns and their relatives)
Originated about 300 million years ago
developed vascular tissue that allowed them to grow tall
Sporophyte (diploid) generation becomes dominant stage in life cycle
Gametophytes are short-lived and require moisture to carry out sexual reproduction

14. Seedless Vascular Plants
Whisk Ferns (Psilotophytes)
Look like small green whisk brooms
No leaves or roots
Short rhizomes, which are horizontal, underground stems.
Produce spores.
Club Mosses (Lycopodophytes)
Small evergreen-looking plants that grow in dense mats in moist temperate or tropical forests.
Not related to true mosses!
Have true roots and stems.

15. Horsetails (Sphenophytes)
Once included tree-sized members, but now just smaller plants (1 m).
Often found in damp areas or along roadsides.
Can be used to scour pots.
Have silica in their cells, which accounts for the roughness.
Can be made into a shampoo to combat head lice.
Ferns (Pteridophytes)
Dominated the forests during the Carboniferous period ( mya).
Most familiar and successful of the seedless vascular plants.
Have roots, stems, a waxy epidermis that reduces water loss by evaporation and stomata in their leaves for gas exchange.
Ferns produce millions or even billions of spores in their lifetime.
Have fronds, which are seed leaves that grow up from rhizomes.

16. 3) Gymnosperms (Conifers)
disperse by means of seeds
reproduce sexually without needing water and different than other 2 groups.
have seeds that are exposed on the surface of cone scales
gymnosperm means ‘naked seed’
includes cone-bearing trees: pines, firs, spruce, yew, cedars, redwood and many other large trees.
Also includes the cycadophytes, gnetophytes and ginkgophytes.

17. 3) Gymnosperms Conifers
Largest group of gymnosperms. Form vast forests in the colder regions of the world
Covering of bark helps protect the stem and reduce water loss.
Have a pyramidal shape and flexible branches to help snow and ice slide off the tree reducing branch breakings.
needle like leaves have a thick, waxy cuticle and sunken stomata, which reduce the rate of evaporation.
Most conifers are evergreens, so they continually lose and replace their needles all year round.
Better able to grow in nutrient poor soils because they do not need to grow a complete set of leaves all at once.

18. Gymnosperms cont. Gnetophyta Very rare, found in southern Africa
May live 100 years. Produces two broad leaves that it keeps its entire life.
Cycadophyta
Short, palm-like trees with scaly trunks. Mainly exists in the tropics. Common trees when dinosaurs roamed the earth.
Ginkgophyta
Distinctive lobed leaves.
The only living species is Ginko biloba, which was common during the Jurassic period (200 mya).
Cultivated in Asian temples for hundreds of years, which helped protect against extinction.

19. 4) Angiosperms (Flowering Plants)
Plants that protect their seeds within the body of a fruit are called angiosperms or flowering plants.
Include vines, grasses, shrubs, trees and water plants.
Grow almost everywhere on land from tundra to tropics.
Flower contains sexual reproductive structures, use wind, water, animals, bats, birds and insects as pollen carriers.
Divided into monocots (1 seed leaf) and dicots (2 seed leaves). Seed leaves (cotyledon nourish the growing embryo
 Appeared on earth more than 150 mya. More than ¾ of all species of living plants!

20. Monocots vs. Dicots