Introduction to Plants

To Introduce Make a list of five plants you might eat during a typical day Which part of the plant are you eating when you eat that plant?

To Introduce Brainstorm a list of products you use that originate from plants…….

Plants differ from Algae All plants are multicellular and develop tissues

Why are plants so important? Photosynthesis…….. They take in CO 2 and Release O 2. What does this do for us?

Characteristics of Plants Many celled Most contain CHLOROPHYLL Cell walls Most have roots or root-like structure Eukaryotic cells Created to live in many different environments 285,000+ species

For Review… Plants are beneficial because they release carbon dioxide. A.True B.False

Adaptations for Land Life 1.Protection and support Cell walls made of CELLULOSE Provide structure and support CUTICLES are a waxy protective layer that also keep plants from drying out

Adaptations for Land Life 2.Reproduction Most land plants do not rely on water in order to reproduce Two stages of reproduction: Sporophyte = plants make spores Gametophytes = plants that grow from spores

For Review… This provides structure and support to a plant. A.Cellulose B.Cuticles

For Review… This structure helps a plant to not dry out. A.Cellulose B.Cuticles

Classification Classified into major DIVISIONS (phyla) (page 244) VASCULAR vs. NONVASCULAR Nonvascular plants do not have special tissues to move water and nutrients through the plant They rely on DIFFUSION Small plants

Divisions Seedless & Seed Plants Bryophyta - nonvascular plants –Class Musci - the mosses Pterophyta - ferns, seedless plants Spenophyta – horsetails and scouring rushes

Divisions Ginkgophyta – ginkgos Cycadophyta – cycads Gnetophyta – gnetums

Divisions Lycophyta – club mosses Coniferophyta - cone-forming seed plants Anthophyta - fruit-forming seed plants (Angiosperms) –Class Monocotyledonae - plants with one seed leaf –Class Dicotyledonae - plants with two seed leaves

Seedless Plants

Seedless Nonvascular Simple plants –Few cells thick –No roots –No stems –No leaves –No flowers –Grow from spores –Mosses and Liverworts

Mosses Simple rootless plant with leaf-like growths in a spiral around a stalk RHIZOIDS = root- like threads made of a few long cells Osmosis

Liverworts “herb for the liver” Rhizoid made of one cell Like mosses, grow in damp areas WHY???

Moss Life Cycle Page 277 in your text book ALTERNATION OF GENERATIONS = continuous cycle which alternates between spore and sex cell producing phases tent/animations/content/moss.htmlhttp:// tent/animations/content/moss.html

Moss Life Cycle Moss appears as soft green carpet GAMETOPHYTE = sex-cell producing structure –May produce male, female or both –Via water male sperm splashed onto female part and swim to eggs Fertilized egg develops into zygote (diploid) that will grow into the sporophyte SPOROPHYTE = spore-producing stage –Stalk and capsule –Capsule will release spores - haploid –Spores germinate into threadlike structure

Importance PIONEER SPECIES –1 st to grow in new or disturbed areas Weathering of rocks Formation of soil Build up decaying plant materials to provide nutrients Pave the way for other plants

For Review… The root-like threads of mosses A.Hyphea B.Rhizoids C.Sori D.Sporophyte

For Review… The stage in a mosses life cycle that produces the sex-cells. A.Gametophyte B.Sporophyte

For Review… Mosses are considered a pioneer species because A.They ride in covered wagons B.They grow in an area after other species of plants begin to grow C.They help create soil in new or disturbed areas

Seedless Vascular Have vascular tissue Produce spores Tube like vascular tissue to carry water, minerals, and nutrients throughout plant How is this an advantage? Club mosses, spike mosses, horsetails, ferns

Club and Spike Mosses Produce spores at end of stems Lycopodium used for décor Resurrection Plant

Horsetails Jointed stem “scouring rush” Used by pioneers to scour pots and pans (silica)

Ferns Largest group in Pterophyta Produce spores in SORI on back of leaves Coal is formed from plant build up over long period of time BOG = Spongy wet ground of slowly decaying plants = Peat fuel –Bryophytes and ferns

Fern Life Cycle Page 279 in your text book RHIZOME = underground stem FROND = leaf of a fern SORI = spore cases Spores released to damp soil will germinate into heart shaped gametophyte plants = PROTHALLUS This will produce sex cells to form a zygote Sporophyte and gametophyte can survive on their own

Importance House plants Prevent soil erosion Some are edible Horsetails: Dietary supplements Shampoos Skin-care products

For Review… The spore cases of a fern A.Sori B.Sporangia C.Rhizome D.Frond