bio cram 2

similarities of land plants (green algae)

• Chloroplast structure

• Cellulose cell walls

• Peroxisome enzymes (↓ photorespiration)

• Flagellated sperm

differences of land plants

• Alternation of generations

• Walled spores (sporangia)

• Chloroplast structure

• Cellulose cell walls

bryophytes

gametophyte, no tissue, small, has rhizoids

sporophyte

vascular, xylem & phloem, can be tall, true roots

how plants changed earth

oxygen rose and carbon dioxide fell, prevented erosion, created habitats, and formed coal

life cycles of bryophytes

gametophyte dominant

life cycle of vascular plants

sporophyte dominant

innovations of life cycle

reduced gametophytes, heterospory, and seeds

advantages of embryos

develops inside parent, protection & nutrients, and better survival on land

microphylls leaves

small, 1 vein

megaphylls leaves

large, branched veins

benefits of seeds

protection, food supply, dormancy, and dispersal

plant evolution trend

algae- bryophytes - vascular - seed plants

gymnosperms

naked seeds. adapted to dry land

types of gymnosperms

cycads (topical), ginkgo (living fossil), conifers (pine)

angiosperm parts

sepals (protection), petals (Attraction), stamens (pollen/male), capels (ovules/female)

angiosperm success

flowers pollenate, fruits disperse seeds

secondary chemicals in angiosperm

alkaloids (defense), terpenes (attract/defend), phenolics (UV protection)

coevolution example

flowers to pollinators, fruits to animals

monocots

1 cotyledon, parallel veins, floral organs in 3s

eudicots

2 cotyledons, net-like veins, floral organs in 4s/5s

shoot systems

stems and leaves

root systems

anchors + absorbs

types of roots

fibrous, taproot, storage

how are roots controlled

signaling proteins

plants needs

light, H2O, CO2

nutrients plants need

nitrogen, phosphorus, potassium, micronutrients

organic matter in soil

nutrients and water, nitrogen must be fixed

nutrient sources (symbiotic)

nitrogen fixing bacteria, mycorrhizae (fungi help roots)

other strategies of symbiotic nutrition

carnivorous plants eating insects, parasitic plants stealing nutrients