Plants Chapter 19 & 20
The origin of plants from algae Desended from Charophytes (multicellular green algae) Live around edges of lakes and ponds Some ancient charophytes may have lived in shallow-water habitats that occasionally dried out Natural selection favored algae that could survive the dry periods Adaptations enabled permanent plant life on dry land 475 million yrs ago
What are plants? Multicellular Autotrophic Embryo develops within a mother plant Eukaryotic
2 (phyla) divisions in plants 19 Mosses, hornworts, liverworts 2 (phyla) divisions in plants 1. Bryophytes- do NOT have transport tissue called vascular tissue, thus are nonvascular plants 2. Tracheophytes- do have vascular tissue, so are called vascular plants Flowering Plants conifers Ferns
Warm-up: (solo on scratch paper) Identify the 2 phyla/divisions of plants Identify the characteristic that separates plants into these 2 divisions Identify major examples of plants that belong to each division
19 Bryophytes Nonvascular plants grow close to the ground to absorb water and nutrients. Seedless plants rely on free-standing water for reproduction. Liverworts, Mosses Hornworts
3 Kinds of Tracheophytes 19 3 Kinds of Tracheophytes Pteridophytes : Gymnosperms Angiosperms
Adaptations of tracheophytes to life on land 19 Tracheophyte Facts Adaptations of tracheophytes to life on land 1. P- protection from drying out 2. E- exchange of gases through leaves 3. T- transport substances 4. S- support
Plants have adaptations that allow them to live on land. 19 Plants have adaptations that allow them to live on land. P-protection from drying out A cuticle allows plants to retain moisture. waxy, waterproof layer holds moisture in
Plants have adaptations that allow them to live on land. 19 Plants have adaptations that allow them to live on land. stoma Gurard cell E-Exchange of gases on leaves Stomata are tiny holes in the lower epidermis. Guard Cells- open & close stoma
Plants have adaptations that allow them to live on land. 19 Plants have adaptations that allow them to live on land. T- Transport by Vascular Tissue Xylem: transports water and minerals up from roots to leaves Phloem: transports food (glucose) from leaves to roots and shoots sugars water and mineral nutrients xylem phloem
Plants have adaptations that allow them to live on land. 19 Plants have adaptations that allow them to live on land. S- support by cellulose and Lignin plant cells lignin Allows plants to grow upright hardens cell walls of some vascular tissues provides stiffness to stems
Bryophytes Nonvascular plants grow close to the ground to absorb water and nutrients. Seedless plants rely on free-standing water for reproduction. Liverworts, Mosses, and Hornworts VIDEO Alternation of Generations: The sex life of Bryophytes What is meant by “Alternation of Generations”? What is the difference between gametophytes and sporophytes?
Pteridophytes (Club mosses and ferns) are seedless vascular plants. 19 Tracheophyte #1 www.brainpop.com/science/diversityoflife/seedlessplants/ Pteridophytes (Club mosses and ferns) are seedless vascular plants. Characteristics/Adaptations: Vascular tissue Seedless Ferns, Club Mosses, and Horsetails Club Moss Fern Horsetails
19 Ferns Sori form under the fronds Rhizoids Rhizomes Fiddlehead Fern Life Cycle: What are Rhizoids What is the difference btwn antheridium and archaegonium? What is the function of anteridiogen? Video
video 19 Gymnosperms Tracheophyte #2 www.brainpop.com/science/diversityoflife/seedplants/ Gymnosperms Plants that bear seeds that are “Naked” (not enclosed by an ovary) can reproduce without free-standing water, via pollination ADAPTATIONS Vascular Tissue Pollen Grains (male gametophyte) Naked Seeds (embryo & food supply) seeds allow plants to disperse to new places video Vascular Plants
19 Gymnosperms do have naked seeds (not enclosed by a fruit). CONIFERS CYCADS GINKGOS
video 19 Tracheophyte #3 Angiosperms (flowering plants) Adaptations: vascular tissue Flowers (reproductive structure) Seeds develop within ovaries Fruit- ripened ovary
19 Structure of a Flower
Monocots VS Dicots Work with your face partner… Create two lists that describe the characteristics of monocots and dicots
Classes of Angiosperms 19 Classes of Angiosperms 1 cotyledon DICOTS 2 cotyledons
Monocots and Dicots (classes of Angiosperms) 19 Monocots and Dicots (classes of Angiosperms) lily Oak tree grass Cherry Tree
Fig. 19-5 Which group of algae has been hypothesized to be the ancestor of plants? Which group of plants evolved most recently? What main adaptation separated the pteridophytes from bryophytes? In which group of plants did seeds first appear?