kingdom plantae
DESCRIPTION
Kingdom Plantae. General Characteristics. Use photosynthesis to gain energy, therefore autotrophic. Live in all aquatic and terrestrial habitats except at the poles. Are the main source of oxygen for the planet The basis for every food chain or food web. Classification of Plantae. - PowerPoint PPT PresentationTRANSCRIPT
General CharacteristicsGeneral Characteristics
• Use photosynthesis to gain energy, therefore autotrophic.
• Live in all aquatic and terrestrial habitats except at the poles.
• Are the main source of oxygen for the planet
• The basis for every food chain or food web
Classification of PlantaeClassification of Plantae
• Although there are a vast variety of plants in the world, they can all be placed in one of four main groups.
• Each large group contains several divisions, which are the rough equivalent to a Phylum.
1) Non-Vascular Plants (Mosses 1) Non-Vascular Plants (Mosses and their relatives)and their relatives)
• Three divisions (mosses, hornworts and liverworts).
• No vascular tissue, therefore 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.
• Sexual reproduction.
Non-vascular PlantsNon-vascular PlantsMosses (Bryophytes)• Very successful and widespread as
they 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!
Liverworts (Hepatophytes)• Grow flat, low to the ground and are
rarely more than 30 cells thick.• 80% are leafy and live in tropical
forests and in humid climates.• Thallose liverworts are the other 20%.• Many small chloroplasts per cell.
Hornworts (Anthocerophytes)• Broad, flat and are commonly blue-
green in colour.• One large chloroplast per cell
2) Seedless Vascular Plants (Ferns 2) Seedless Vascular Plants (Ferns and their relatives) and their relatives)
• came about 300 million years ago• developed the vascular tissue that allowed them
to grow tall
Seedless Vascular PlantsSeedless 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.
Seedless Vascular PlantsSeedless Vascular PlantsHorsetails (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 (315-280 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.
3) Gymnosperms (Conifers and 3) Gymnosperms (Conifers and their relatives) their relatives)
• disperse by means of seeds• reproduce sexually without
needing water• 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.
GymnospermsGymnospermsConifers• Form vast forests in the colder
regions of the world• As well as reproducing without
water, they have bark to prevent water loss.
• The pyramidal shape of many conifers helps snow and ice slide off the tree reducing branch breakings.
• The needle like leaves have a thick, waxy cuticle and sunken stomata, which reduce the rate of evaporation.
• These are evergreens, which are continually losing and replacing needles all year round.
Gnetophyta• Very rare, found in southern Africa
GymnospermsGymnosperms
Cycadophyta• 100 species in the tropics,
once dominated the earth.• Short, palm-like trees with
scaly trunks.
Ginkgophyta• 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.
4) Angiosperms (Flowering Plants) 4) Angiosperms (Flowering Plants)
• Plants that protect their seeds within the body of a fruit are called angiosperms or flowering plants.
• Appeared on earth more than 150 mya.
• Include vines, grasses, shrubs, trees and water plants.
• Grow everywhere on land from tundra to tropics.
• Divided into monocots (1 seed leaf) and dicots (2 seed leaves)
• Sexual reproduction by pollination. Use wind, water, animals, bats, birds and insects as pollen carriers.