Transcript On-level - Fulton County Schools

Plant kingdom
diversity
Plant groups
 Bryophytes (seedless, non-vascular)
 Seedless vascular plants
 Gymnosperms
 Angiosperms
Cladogram
Gymnosperms
Angiosperms
Seedless vascular
plants
Bryophytes
Evolution of specialized
cells / tissue
Green algae
Evolution of cuticle
Bryophytes
 think moss
Bryophytes
 Small
 Found only in damp, moist areas on land
 1) Leaves must touch water for photosynthesis
 2) Sperm swims through water to reach egg
in gametophyte
Bryophytes
sporophyte
gametophyte
Alternation of generations
mitosis
Multicellular
sporophyte
diploid organism
(2n)
meiosis
Unicellular
diploid zygote
(2n)
fertilization
Unicellular
haploid gametes
(n)
Multicellular
haploid organism
mitosis
(n)
Unicellular
haploid cells
(spores)
(n)
mitosis
gametophyte
Cladogram
Gymnosperms
Angiosperms
Seedless vascular
plants
Bryophytes
Evolution of
vascular tissue
Green algae
Evolution of specialized
cells / tissue
Evolution of cuticle
Vascular tissue
 Set of tubes that transport materials
around plant
 Allows plants to grow taller
 Water travels up through xylem
 Sugar travels throughout in phloem
Seedless vascular plants
 Think ferns
Ferns live further on land
 Still must be in moist areas
 Sporophyte survives fine with vascular
tissue
 But sperm must still swim to egg in tiny
gametophyte
Fern gametophyte
Cladogram
Gymnosperms
Angiosperms
Seedless vascular
plants
Bryophytes
Evolution of
pollen grains /
seeds
Evolution of
vascular tissue
Green algae
Evolution of specialized
cells / tissue
Evolution of cuticle
Pollen grains
 Hard covering around sperm, light weight
allows travel by wind
 Removes water requirement for
fertilization
Sperm still swims
 At the very end when
pollen lands on
another plant of
same species
 Pollen tube connects
to ovary, sperm swim
to egg
Full colonization of land
 Vascular tissue
+
 Reproduction through air
Seeds
 Tough coat protects newly fertilized
embryo
 Also contains supply of food (endosperm)
to survive during dormancy period
Gymnosperms
 Think cones (any conifer like pine trees)
female ovary
male pollen cone
Gymnosperm pollen
strategy
 Release a lot, hope some pollinate
 (Meanwhile, irritating everyone else)
Cladogram
Gymnosperms
Angiosperms
Evolution of
flowers / fruits
Seedless vascular
plants
Bryophytes
Evolution of
pollen grains /
seeds
Evolution of
vascular tissue
Green algae
Evolution of specialized
cells / tissue
Evolution of cuticle
Angiosperms
 Think flowers (most diverse plant group)
Flowers
 Attract animals to help carry pollen to the next
flower
 Color or scent attractors guide animals to
obtain sugar from plant
 Oh, and while you’re at it, grab some pollen
 Some angiosperms still wind pollinate (grass)
Advertising in UV color
After fertilization, ovary
becomes fruit
Fruit
 Typically collects sugar to attract animals
 Seeds survive animal digestive system,
pooped out far away from parent (and
with free fertilizer!)
 Some are not eaten by animals, just help
wind carry seed (dandelion)
Asexual reproduction
 Plants can also reproduce asexually
 Many plant parts can regrow to make a
whole new organism when separated
(vegetative reproduction)
Cladogram
Gymnosperms
Angiosperms
Evolution of
flowers / fruits
Seedless vascular
plants
Bryophytes
Evolution of
pollen grains /
seeds
Evolution of
vascular tissue
Green algae
Evolution of specialized
cells / tissue
Evolution of cuticle