1. National Geographic - Plants
Kingdom Plantae
National Geographic - Plants

2. Kingdom Plantae
What are plants?
most are autotrophs
eukaryotic
have cell walls containing cellulose
mostly land dwelling organisms
they are the foundations of almost all ecosystems.

3. Plants
Non-flowering
Flowering
1 seed-leaf
2 seed-leaves
Spore-bearing
Naked seeds
Monocots
Dicots
Gymnosperms
No roots
with roots
Mosses
Ferns

4. Evolution of Plants
ancestors of modern day plants were aquatic organism similar to green algae.
to grow on land, plants have developed:
an embryo – reproductive structure which develops directly into a plant.
ability to stand upright and reach for the sun
tissues to transport water, nutrients and wastes.
strategies to reduce water loss
strategies to disperse seeds without relying on water currents.
flowering plants are the youngest in plant evolution.

5. Alternation of Generations
most plants have a life cycle that alternates between diploid and haploid forms.
diploid (2 sets of chromosomes – 1 from each parent)
haploid (1 chromosome set)

6. Classification of Plants:
there are 5 major groups of plants:
green algae
mosses and relatives
ferns and relatives
seed plants
flowering plants

7. Green Algae – modern relatives of plant ancestors
many species are found in shallow fresh water – edges of ponds
Mosses and Relatives – seedless non-vascular plants
(Bryophytes)
grow close to the ground in damp locations where can easily obtain water.
no seeds or stems – no rigid support structures in cell walls, so can’t grow tall.
non-vascular – can’t transport water or nutrients within.
male and female gametes are produced in separate reproductive structures - sperm have flagella and swim through water to the eggs.

8. Spore-producing capsule
Mosses

9. Ferns and Relatives – seedless vascular plants
have vascular structures to carry water.
gives advantage: can grow taller – reach the sunlight
vascular structures (veins) connect shoots above ground to roots below
seedless: reproduce much like mosses – sperm swims to egg on a film of water on the underside of the plant.

10. Gymnosperms – seed plants
conifers (pine, fir, cedar, ginko)
‘naked seeds’ – not protected or enclosed in an ovary.
seeds are plant embryos packaged in a protective coat along with a food supply.
pollen grains are small male gametophytes that contains cells that develop into sperm.
wind carries the pollen grains to female cones – where eggs develop.

11. Angiosperms – flowering plants
reproductive structures are flowers
2 groups: monocots and dicots
ovaries within flowers completely protect the seeds.
gametophytes of angiosperms develop within the flowers
flowers have many adaptations to disperse pollen and seeds.
insects, animals, birds (and wind) all transfer pollen from one flower to another.
once pollination occurs the ovary develops into a fruit – the ripened ovary of a flower.
fruits are a good way to disperse seeds:
if ingested, the seed survives and drops elsewhere
burrs stick to animal fur.
maple keys are suited to wind dispersal
coconuts are well suited to water dispersal

12. Flowering Plants
Monocotyledons
Dicotyledons