Ch. 30 Plant Evolution & Classification

1. Ch. 30 Plant Evolution & Classification • The first plants were thought to be water plants  Algae. Other plants evolved from algae. • If you were to take algae out of the water would it live alright. • So, how do land plants live away from water? • Land plants developed a cuticle, which is a waxy protective covering, to protect against desiccation. Bark & leaves have this. • Does algae have a cuticle? • Algae is not a plant; it’s classified as a Protista

2. Vascular Tissue • Vascular tissues transport food and water throughout the plant. • 1. Xylem – transports water. Dead cells. • 2. Phloem – transports food. • Table 30-1 Phyla of the Plant Kingdom • Nonvascular • Vascular without seeds • Vascular with seeds • Spores – haploid reproductive structure of some plants. • Seeds – diploid (embryo) structure with a protective coat and endosperm (food).

3. 2 Main Groups of Plants • 1. Nonvascular plants – no vascular tissue. No true roots, leaves, or stems. • Ex. Bryophyta  Mosses • 2. Vascular plants – have vascular tissues. Able to transport food & water. They have true roots, leaves, and stems. • Pterophyta  Ferns (spores - seedless) • Shenophyta  Horsetail (spores - seedless) • Coniferophyta  pine trees (gymnosperms). • Anthophyta  flowering plants (angiosperms).

4. Bryophyta are mosses that have rhizoids. Rhizoids (false roots) are like roots, but they don’t have vascular tissue. How many of you get moss on your fishing line when you go fishing? • Horsetails have a cone-like structure at the tip called a strobilius. • Horsetail is also called scouring rush; Native Americans use to use it for clean pots. • Name the main types of vascular plants • Horsetail, ferns, conifers, flowering plants

5. Parts of a Fern • Fern’s leaves are called  Fronds • Fern’s roots are called  Rhizomes • On the underneath side of a frond are several round structures called  sori (plural). • The outside covering of the sori is a induisium. The induisium opens up to release sporangium. • The sori hold several sporangium. Inside the sporangium are spores, which are released when the sporangium opens up. • Types of ferns  Pg. 587

6. Gymnosperms • Gymnosperm means “naked seeds”. • Gymnosperms have cones with seeds. • Ginkgo trees are one of very few deciduous tree that are gymnosperms. • What does deciduous mean? • Has anyone ever heard of a ginkgo before? • Conifers or evergreens are the main type of tree in this group  Coniferophyta. • Oldest living organism – Bristle Cone Pine – 4,000 to 5,000 years old. • One of the most massive organisms – Giant Sequoia – about 100,000 tons.

7. Angiosperms • Angiosperms – means “covered seeds”. • Anthophyta (division) – Flowering plants • Divided into 2 Classes • 1. Monocotyledon (Monocots) – 1 seed leaf or 1 cotyledon • 2. Dicotyledon (Dicot) – 2 seed leaves or 2 cotyledons.

8. Monocot Characteristics • 1. Parallel leaf venation. Ex. Corn & grasses • 2. 3 or 6 part arrangement of the flower • 3. 1 cotyledon • 4. Scattered vascular bundles • Examples = grasses, wheat, corn, tulips, etc. • Dicot Characteristics • 1. Netted leaf venation. Ex. Most tree leaves • 2. 4 or 5 part arrangement of the flower • 3. 2 cotyledon • 4. Vascular bundles in a ring. • Examples = trees, most weeds, etc.

9. What does the term deciduous mean? • Trees that loose their leaves. • Alternation of Generation • This is the life cycle of plants (2 phases) • 1. Sporophyte Generation (Diploid) • The time when the plant produces spores or seeds • This is the mature part of the plants life cycle. • 2. Gameophyte Generation (Haploid) • The time when the plant produces an egg and pollen (gametes). • This is the part of the life cycle when there is a antheridium (male plant) and archegonium (female plant). • When the male (pollen ) fertilizes the female (egg), that starts the sporophyte generation again. • Pg. 582

10. Seeds vs. Spores • 1. Seeds have a constant supply of food for the embryo from the cotyledon. • 2. Seeds are protected during harsh conditions. • Drought & winter • 3. Seeds adapt for easy dispersal. • Stickers, dandelion, fruit, ect. • 4. Seeds don’t require water. • So, how do spore plants survive if spores have less advantages? • Produce more spores