LEC
01
Plant Evolution
&
Diversity
Overview
LOCAL FLORA – Lecture 01
Dr. Donald P. Althoff
ANGIOSPERMS
SEEDS & FRUITS (not ___________)
Algae-to-Plants: Land Conquered
• _______ or rootlike structures
• Conducting _________
• Stiffening substance __________
• Waxy ___________
• Pores called ____________
mosses
ferns
conifers
Flowering
plants
________
______
_____________
_______________
protista
*Algae—plant-like _________ organisms
Reproduction on land “key”
• Needed to have new method to
transport sperm to eggs
• Accomplished by having sex cells carried
by _____…or ____…or ________
• And, _______ of developing embryos from
__________...
Evolutionary process…con’t
• First, ________
• Followed by _______…
• Then, in the most advanced plants,
________________
ALTERNATING GENERATIONS
Gametophyte = (n) produces gametes
Sporophyte = (2n) production of spores by meiosis
Think 4 Major Divisions
 Bryophyta
 Pteridophyta
 Coniferophyta
 Anthrophyta
•
•
•
•
•
~16,000 species
_____ true roots, leaves & stems
root equivalent -- RHIZOIDS
____________ plants
rely on diffusion or poorly developed
conducting tissues to distribute water &
nutrients
NON-vascular plants
Division: Bryophytes
LIVERWORTS & MOSSES
LIVERWORTS & MOSSES…con’t
• most are _______ (2cm) max height
• main adaptation to land:
_____________
REPRODUCTIVE
STRUCTURES
archegonia (egg develops)
antheridia (sperm formed)
LIVERWORTS & MOSSES…con’t
• sperm must swim to egg through a ____
___________
• egg emits a _______________ to aid in
location by the sperm
• timing of reproduction MUST coincide
with _________________…this is very
__________ in dry environments
• Seedless:
Club mosses,
horsetails, &
ferns
• Seed-bearing: Conifers (pines)
flowering plants
vascular plants
VASCULAR PLANTS
(3 MAJOR CATEGORIES)
Vascular, ___________ bearing plants
FERNS & CLUB MOSSES
• PTERIDOPHYTA—ferns
most successful
(~12,000 species)
• LYCOPHYTA--club mosses
(ground pine)
(~1,000 species)
• SPENOPHYTA--horsetails
(~15 species)
FERNS & CLUB MOSSES…con’t
• Distribution and dominance-wise, these plant
divisions _____ seen better days…
• Life cycles, again, tied to moist conditions…
ex: dominant plant body for ferns
is the sporophyte (frond)
Non-flowering, seed bearing plants
Plants PINES, GINKGOS, & CYCADS
• Pines (~500 species) (Conifers)
• Ginkgos (1 species: Ginkgo biloba…
can you remember this one?)
-- male & female trees
-- extinct in wild
-- resistant to air pollution
• Cycads (~160 species)
Conifers = EVERGREENS
(Division: Coniferophyta)
• Gymnosperm = “____________” in Latin
• Pines, spruces, firs, hemlocks, & cypresses
• Once more ______________ and dominant on
land
• Most are extremely well-adapted to _____(cold),
____ conditions….
Conifers…con’t
• Dry & cold environment adaptations:
a) thin needles with ______ cuticle
b) _____ contains “antifreeze”
(what gives it a “piney”
fragrance)
• How do these adaptations help????
Conifers…reproductive cycle
• Dominant form: _____ = diploid sporophyte
• Male & female cones
• Pollen (from male cones) dispersed by
wind
• Pollen landing on scale of female cone
produces pollen tube that burrows into
female gametophyte
Flowering Seed Plants
ANGIOSPERMS
• Division: ANTHROPHYTA
(“anthro” is Greek for “_______”)
• “Angiosperm” is Greek for “________
___________________” ….angiosperms
produce their seeds enclosed within a fruit
• Diverse group….corn, oaks, water lilies,
cacti, and buttercups
Angiosperms…con’t
• ~230,000 species
• “the” ________ plant division for over 100
million years
• 3 major adaptations:
a)
1 flowers
2 fruits
b)
c)
3 broad leaves
1
Flowers
• Produced by sporophyte
• Males & females generally in same
flower
• _______ formed in anther (male)
• _______ formed in ovary (female)
• Fertilization accomplished with pollen
tube through the stigma
All in!
2
Fruit
• Contains the ovary which contains a
______________
• This adaptation greatly enhanced
__________.most seeds pass through
digestive tracts of animals unharmed.
Some attached to fur.
Seeds
• Important source of food for
humans….including prehistoric times
a) easy storage (if kept dry)
b) source of protein, oils,
carbohydrates, & vitamins
…same goes for
germinating seed
3
Broad Leaves
• During favorable conditions…particularly in
tropical and temperate zones…_____
______________ available to collect
sunlight for photosynthesis.
• Excess production allows for storage…and
subsequent dormant period
Broad Leaves…liabilities
• Broad, ________ leaves are more appealing to
herbivores than conifer leaves (needles)
• To __________….some have developed
defenses:
a) thorns, spines, & resins
b) chemical compounds that
may be toxic or distasteful
mosses
ferns
conifers
Flowering
plants
Flowers
Seeds
Vascular tissue
All multicelluar
protista
*Algae—plant-like single-cell organisms