Plant DiversityPlant Diversity(its not an old wooden ship)(its not an old wooden ship)

Chapter 29-30Chapter 29-30

Objectives:

1. Understand the 4 main phyla of plants

2. Understand the evolutionary history of plants

3. Look at key adaptations in different groups of plants

1. Four phyla of the plant kingdom1. Four phyla of the plant kingdom

a) Bryophytes (mosses) – 18,000 extant species, non-vascular plants

b) Pteridophytes (ferns) – 13,000 species, seedless, vascular plants

c) Gymnosperms (cone-bearing) – 721 species, vascular plants with seeds contained in cones (naked seed)

d) Angiosperms (flowering plants) – 250,000 species – vascular plants with seeds contained in flowers/fruit

Intertidal ZonesIntertidal Zones

2. Charyophyceans and Land 2. Charyophyceans and Land plantsplants

Similiarities

1. Rose-shaped proteins that make cellulose

2. Peroxisome enzymes (photorespiration)

3. Sperm structure

4. Formation of cell plate

5. Homologous chloroplasts (DNA)

3. Terrestrial Adaptations3. Terrestrial Adaptations

• Apical meristems (roots/shoots) – better exposure to resources

• Multicellular, dependent embryos – better protection

• Alternation of generations – produces more spores (delayed meiosis?)

• Walled spores – sporopollenin – most durable organic material known

• Multicellular gametangia – produce many gametes

• Cuticle, stomata, vascular tissue

SporopolleninSporopollenin

Alternation of GenerationsAlternation of Generations

BryophytesBryophytes

• Liverworts, hornworts, mosses

• Protonema – 1 cell thick

• Non-vascular

• Anchored by rhizoids (no water uptake)

• Prefer moist environments

• Gametophyte generation - dominant

Moss SporophytesMoss Sporophytes

Moss animationMoss animation

http://www.sumanasinc.com/webcontent/animations/content/moss.html

Moss Life Moss Life CycleCycle

Pteridophytes (ferns)Pteridophytes (ferns)

• Ferns are the most abundant group of seedless vascular plants

• 75% of species occur in tropics

• Sporophyte generation is dominant (gametophyte usually hard to find)

• Frond – leaf• Rhizome – underground

stem• Sori (sorus) – clusters of

sporangia (produce spores)

Pinnae

FiddleheadsFiddleheads

Fern Life cycleFern Life cycle

SoriSori

Gametophyte (prothallus)

Young sporophyte

Objectives (Day 2)Objectives (Day 2)

• Understand the evolutionary significance of seeds, pollen, and vascular tissue

• Understand the pollination and fertilization of seed plant

Seed PlantsSeed Plants

9. Reduced gametophyte – able to be protected inside parental sporophyte for nutrition and protection (UV light)

- Spores are now contained inside sporophyte

10. Seeds10. Seeds

• Plants can live in more diverse terrain

• Protects embryo from harsh environments

• Allows for better seed dispersal

11. Pollen11. Pollen

• Tough outer coat of sporopollenin

• Male gametophyte• Able to travel large

distances (reach other plants), created more genetic diversity (gene flow)

• Specific for each species of plant

12. Gymnosperms12. Gymnosperms

• 30.8• 30.4

Gymnosperm Life CycleGymnosperm Life Cycle

13. Angiosperms13. Angiosperms

• 30.11

Monocots/DicotsMonocots/Dicots

14. Flowers14. Flowers

• Pollination is less random

• Protects embryo

Types of fruitTypes of fruit

16. Seed Dispersal16. Seed Dispersal

• Fruit has propellers – dispersed by wind

• Burrs, hooks – animal fur

• Tasty fruit – digestive tract of animals

Exceptions to the ruleExceptions to the rule

• Complete flowers• Incomplete• Bisexual (perfect,

monoecious)• Unisexual (imperfect,

dioecious)

Flower DiversityFlower Diversity

• Coevolution – pollinators

Pollination/FertilizationPollination/Fertilization• Pollination – pollen

travels from anther to stigma

• Fertilization – pollen travels from stigma, through style, and fuses with egg inside ovary

• Plants can prevent self-fertilization (preserve genetic variation)

Gametophyte developmentGametophyte development

Due MondayDue Monday

• Ch. 39 reading guide

• 8 diagrams