Plants Cellulose cell walls Almost all photoautotrophic Nearly all terrestrial 295,000 Species

Vascular vs. Non-Vascular Vascular- have internal tissues that conduct water –Xylem- Transports water –Phloem- Transports sugars Non-Vascular- lack these tissues –Ex: Mosses

Roots and Shoots Shoots-stems and leaves, absorb energy and CO 2 Roots- underground absorptive structures

Plant Sex (Alternation of Generation)

zygote SPOROPHYTE (2n) GAMETOPHYTE (n) GREEN ALGABRYOPHYTEFERNGYMNOSPERMANGIOSPERM

Most plants are hermaphrodites, both male and female Seedless plants- ferns, horsetails Seed-bearing plants –Seeds- ‘A baby in a box with a lunch’ –Gymnosperms- open fertilization Conifers and Ginkos –Angiosperms- closed fertilization Flowering plants Making Babies

Baby in Box With a Lunch

Fern Lifecycle

Parts of a flower

Non-Vascular Plants –Bryophytes- 18,600 species Mosses, liverworts and hornworts The simplest plants Non-vascular All <8 inches tall Many have rhizoids

Bryophytes (mosses)

Seedless Vascular Plants Whisk Ferns, Lycophytes, Horsetails and Ferns They have true vascular tissue. Most live in wet, humid places and the gametophytes lack vascular tissues.

Sporophyte of Lycopodium Figure 15.8a Page 253 Do not post to Internet

Equisetum Do not post to Internet

Tree ferns (Cyathea) Do not post to Internet

Seed-Bearing Plants Produce Microspores which give rise to pollen Produce Megaspores, which give rise to the egg cells These adaptations are advantages in cooler, drier climates

Conifers Woody trees and shrubs that have cones –Cones- clusters of modified leaves that surround the spore-producing structures Most are evergreen, and a few are deciduous. This group includes the tallest (coast redwoods >100m) and oldest (bristlecone pine 4,725 years old)

Fig (1) Page 257 Do not post to Internet

Conifer Lifecycle

Angiosperms –The flowering plants –260,000 species –The enlarged ovary where the seed develops is the fruit. –Most coevolved with pollinators –Range in size from duckweed ( 100m) –Two Classes Dicots Monocots

Figure Page 258 Do not post to Internet

millions of years ago number of genera other genera 200 ginkgo cycads ferns angiosperms conifers 250

mature sporophyte (2n) ovules inside ovary pollen sac Meiosis Double Fertilization Diploid Stage Haploid Stage seed meiosis and two rounds of mitosis without any cytoplasmic division haploid (n) microspores male gametophyte Pollen is released Pollen tube enters ovule female gametophyte egg haploid (n) megaspore

Fruits