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Introduction to the Plant Kingdom. Aquatic Ancestor. Plants evolved from green algae and they first evolved in water. Chara. Aquatic Ancestor. Algae & Land Plant Similarities Both contain chlorophylls Have chloroplasts with stacks of thylakoids Store starch in plastids
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Aquatic Ancestor • Plants evolved from green algae and they first evolved in water Chara
Aquatic Ancestor • Algae & Land Plant Similarities • Both contain chlorophylls • Have chloroplasts with stacks of thylakoids • Store starch in plastids • Cellulose in cell walls
Plant Characteristics • Multicellular • Autotrophic (photosynthesis) • Surrounded by cell walls containing cellulose (polysaccharide) • Store reserve food as (starch)
Taxonomy • Plants are divided into two groups based on the presence or absence of an internal transport system for water and dissolved materials, called Vascular System Vascular Bundles
Vascular System • Xylem tissue carries water and minerals upward from the roots • Phloem tissue carries sugars made by photosynthesis from the leaves to where they will be stored or used
Nonvascular Plants • Probably the earliest land plants • Do not have vascular tissue for support or conduction of minerals and water • Examples are mosses, liverworts and hornworts
Vascular Plants • Have transportation tubes • Have true roots, stems and leaves • Waxy outer covering called the cuticle protects from drying out
Vascular Plants • Subdivided into two groups -- Seedless vascular plants and Seed-bearing vascular plants Club Moss
Seed-Producing Vascular Plants • Includes two groups – Gymnosperms and Angiosperms • Gymnosperms: which means “naked” seed, are plants that have no protective coat on their seeds- like pine trees • Angiosperms: flowering plants whose ovules are enclosed in an ovary, which is the protective seed coat
Angiosperms • Flowering plants • Seeds are formed when an egg or ovule is fertilized by pollen in the ovary • Ovary is within a flower • Fruits are frequently produced from these ripened ovaries (to help disperse seeds)
Flowers Female Part Male Part