Chapter 23 Plants Page

Adaptations of Plants Absorbing nutrients Preventing water loss Reproducing on land

Advantages of Vascular Tissue Allows for transportation of water Allows for transportation of mineral nutrients

Advantages of Seeds A seed offers a plant’s offspring several advantages: –A. Protection-protects embryo from drying out and from mechanical injury and disease –B. Nourishment-supply of nutrients stored in them

Advantages of seeds (cont) –C. Plant dispersal-ability to be carried away and grow in other places –D. Delayed growth- ability to have suspended animation. To delay growth till favorable conditions.

Advantages of flowers Plant reproduction is more efficienct in the angiosperm plants Attracts animals to have pollen stuck to them to allow greater dispersion Easier cross-pollination can occur in plants living apart

Vascular System of Plants Phloem- is a type of tissue that is soft walled cells that is used to transport organic nutrients Xylem- is a type of tissue that is hard walled cells that transport water and mineral nutrients

Body form of vascular plants Shoots- is the part of a plant’s body that grows mostly upward. Roots- the part of the body that grows mostly downward. Meristems- are zones of actively dividing plant cells

Nonvascular plants Characteristics of nonvascular plants –A. Small size- due to osmosis and diffusion moving water and nutrients –B. Larger gametophyte- are more noticeable than the sporophyte. They also have rhizoids(hairlike projections that they use to anchor plants –C, Require water for sexual reproduction

Kinds of Nonvascular plants Phylum Polytrichum aka Bryophyta- 10, 000 speciesMosses Phylum Marchantia-aka Heptatophyta 6,000 speciesLiverworts Phylum Anthoceros-aka Anthocerophyta- 100 species Hornworts

Seedless Vascular Plants Characteristics –A. Vascular system-the xylem is reinforced with lignin –B. Larger sporophyte- the gametophyte is smaller thus spores are transported easier –C. Drought resistant spores-are resistant to drying therefore can survive in harsher situations

Kinds of Seedless Vascular Plants Club mosses-have roots stems and leaves. Can form cones about 1000 species Horsetails-have roots stems and leaves can have jointed stems,15 species Whisk ferns- highly branched stems but no roots or leaves 3-5 species

Kinds of Seedless Vascular Plants (cont) D. Ferns-have stems, roots and leaves form spores on lower surfaces about 11,000 species

Gymnosperms Characteristics of Gymnosperms –A. Seeds- all gymnosperms produce seeds –B. Small Gametophytes-male gametophytes are pollen, female gametophytes become seeds, mainly develop in male and female cones –C. Wind Pollination- makes sexual reproduction possible even during dry times

Kinds of Gymnosperms A. Conifers-needle like leaves, can be 5,000 years old examples are pines, firs redwood trees, junipers, 550 species B. Cycads- short stems and palmlike leaves, live in tropics 100 species C. Ginkgo- fan shaped leaves, eg maidenhair tree no cones

Kinds of Gymnosperms(cont) D. Gnetophytes- produce pollen and seeds in a cone very diverse 70 species, Ephedra and Welwitschia

Angiosperms Characteristics of Angiosperms –A. Flowers- gametophytes develop with flowers, large variety –B. Fruits- many different types, different methods of dispersion also –C. Endosperms- a supply of stored food a variety of types

Angiosperm families SubgroupFamilyExamples MonocotsIrisIrises, gladiolus, crocus MonocotsLilyTulips,asparagus, aloe vera MonocotsGrassWheat,corn,rice, lawn grasses

Angiosperm families Subgrou p FamilyExamples DicotsAsterDaisies, suflowers, lettuce, DicotsmustardBroccoli, turnips, cabbage DicotslegumesBeans, clovers,peas DicotsroseApples,peaches,pears Dicotsnightsha de Potatoes, tomatoes, peppers, petunias