Transcript Seed Plants connection lesson - biology-rocks

Overview
Plants
Algae
Mosses
Seedless
Plants
LOWER
PLANTS
Ferns
GymnoSperms
AngioSperms
Naked seed
Covered seed
Seed
Plants
Spermopsida
HIGHER
PLANTS
Moving on
• Recap Chapter 20-21
• Next evolutionary step
• Remember  plants are moving to drier
and drier environments
• What are some adaptations?
Plants with Seeds
“Spermopsida”
Chapter 22 p.466
Life on Land
• Benefits
– Abundant sunlight for
photosynthesis
– Continuous free
movement of gases
(O2/CO2)
• Problems
– Scared of:
• drying out
• Finding food while
water and nutrients
only available soil
• How to get sunlight
without a stem
• No water,
reproduction might
not be possible
Adaptations of Seed Plants to
Life on Land
• Vascular tissues (Xylem, Phloem)
• Therefore, developed roots, stems, leaves
• Reproductive adaptations
– free from water
– Use cones, flowers, pollen, seeds**
• **Evolved seeds – a new form of sexual
reproduction (no longer using spores and
water)
• Smaller gametophyte
Roots, Stems
• Roots
– Absorb water and nutrients from soil
– Anchor plants in the ground
– Hold plants upright, prevent plant from
falling over (strong wind and/or rain)
• Stems
– Hold leaves up to the sun
– Provide plant rigidity
Leaves
– Capture sun’s energy
– Covered with a waxy
coating of cuticle
Stomata (p.504)
• Have adjustable openings called stomata that
allows gas exchange but
help conserve water
Vascular Tissue
• Xylem (transports upward)
– Carries water and
minerals from roots
to leaves/stem
– Thick cell walls
provides
strength in woody
plants
– Dead cells
• Phloem (transports up and downward)
– Carries products of photosynthesis
– Cells are alive
Reproduction Free from Water
•
•
•
•
Requires alternation of generations
Dominant generation: diploid (sporophyte)
Gametophytes are small in size
Specialized reproductive structures:
– Flowers and cones
VERY IMPORTANT ADAPTATION
Pollination
• Male gametophytes are contained in small
structures called pollen grain
• Sperms produced don’t
swim but carried by wind,
insects, birds, small
animals, bats
• Pollination: Process of
carrying the pollen to
the female gametophyte
(check out the picture at the beginning of the chapter)
Show TED Pollen Video
Seed Dispersal –
Drop and Scatter
Black Locust Seeds
Sweet Gum
Black Walnut
Seed Dispersal – By Wind
Dandelion
Sycamore
Milkweed
Aster flower
Maple
Aster seeds
Seed Dispersal
• By wind (dandelion)
• Bright berries – seeds
eaten and pass thru
and out animal
• By animal Sharp barbs –
• stick to animal and drop off later
Seeds
• Structures that protect the zygote of seed
plants
• Zygote grows into an embryo
– Found into the seed
– Seed provides food
for the embryo in the
cotyledon
– Embryo may remain
dormant for a
LONG time
Why Stay Dormant?
• In case of extreme climate
– Too cold
– Too hot
– Lack of water (drought)
Seed Coat
• Seed coat surrounds and protects embryo
and prevents the food from drying out
• Protists
– Fungi-like, animal-like, plant-like
– Lifecycle
• Fungi
– 5 classes
– Reproduce with spores, sexual vs asexual
• Plant
– Aglae, mosses, ferns, gymnosperm
– Seeds
– Life cycles
Review
• What is pollination?
• What are the 2 function of stomata?
• What are the 2 main specialized
reproductive structures that evolved?
• What are pollen grains?
Big Idea Review:
Reproductive Adaptations
As plants evolve, 3 important reproductive
adaptations allowed continued success
and diversification of plants in the
terrestrial (land) environment
1) reduction of gametophyte,
2) the presence of the seed,
3) the evolution of pollen