1. Plants

2. Kingdom Plantae Plants evolved about 500 million years ago from simple green algae that lived in the ocean. All plants are autotrophic and some, like the famous Venus fly-trap, can also be heterotrophic.

3. Plant Cells Like animal cells, plant cells contain a nucleus and organelles, but they have two distinguishing features: –Cell wall (made of cellulose - provides rigid structural support) –Chloroplast (conducts photosynthesis)

4. Biodiversity & Plant Diversity Biodiversity refers to the # of different species and the # of individuals within each species Currently over 350,000 species of plants, including: –Mosses –Ferns –Conifers (gymnosperms) –Flowering plants (angiosperms) Most plants live on land and can withstand a wide variety of climates. Cacti live in arid, dry areas whereas mosses need to be in moist environments to survive. High biodiversity in rainforests (warm & wet) and low biodiversity in extreme environments such as arctic and deserts (extreme temp, windy, dry). Loss of a plant species can reduce biodiversity (perhaps it is the only source of food for certain animal species or insects, etc).

6. World Plant Biodiversity

8. Classifying Plants Plants are classified based on: – the presence or absence of vascular tissue –Production of seeds (seed or non-seed) Vascular tissue can be compared to arteries and veins: –a network of specialized cells that allows plants to transport water, minerals and sugar throughout the plant What would you expect a non-vascular plant, without vessels to transport nutrients and water, to look like?

9. VASCULAR PLANTS NON-VASCULAR PLANTS (Bryophytes) DEFINITIO N EXAMPLES STEMS, ROOTS, AND LEAVES? UPTAKE OF WATER AND NUTRIENT S OTHER Network of specialized cells to provide transport of water and nutrients throughout plant No network of specialized cells for transport of water and nutrients throughout plant Flowering plants (angiosperms), conifers (gymnosperms), ferns Mosses & liverworts/hornworts Osmosis, diffusion and active transport Lack true leaves and roots Grow low and close to the ground; must live in moist environments or near presence of water Yes to all Through stems, leaves and roots, and their cells Can grow tall, can live in variety of environments

10. Classifying Plants: Seed or Non- Seed Plants may or may not have the ability to produce seeds as part of their reproductive life cycle –All plants, however, can reproduce sexually and asexually = alternation of generations Seeds are specialized reproductive structures that contain a plant embryo Non-Seed Plants: Mosses & Ferns Seed Plants: Flowering Plants (Angiosperms) & Conifers (Gymnosperms)

12. Seed Plants Important to humans because they provide us with food Why it is advantageous to be a seed plant: –Can sexually reproduce without free water –Can sexually reproduce with another individual far away –Plant embryo surrounded by a protective coat –Seeds can be dormant till environmental conditions are “just right” –Seeds can be carried by wind, water or by animals to other parts of the ecosystem (or even a new ecosystem)

13. Seed Plants Can be grouped into: –Angiosperms (flowering plants). They are grouped further into: Monocots Dicots –Gymnosperms (conifers, etc) More later on!

14. ANGIOSPERMSGYMNOSPERMS TYPE OF PLANTS LEAVES & ROOTS SEEDS ECOSYSTE MS & PRACTICAL USES Woody plants – wood-producing trees & shrubs, conifers including evergreens (pines, firs, cedars, etc) Herbaceous plants – lack woody tissues; flowering plants (some trees can be in this group) Conifers have needles for leaves (small surface area, thick waxy coat = prevents water loss. Roots are shallow & spread out = anchors the tree in areas where soil is sparse. “Naked seed” = no coat Conifers have male and female cones. Pollen grains inside male cone are carried by wind to female cone, where egg is fertilized Boreal Forest and Temperate Rain Forests (hardier than angiosperms) Wood, paper/pulp, varnishes, fuel come from gymnosperms Seed has coat. Male stamen and female pistil (or carpel) on same flower. Pollen from male moves down flower to female part to fertilize the egg. Embryo forms within seed. Diverse ecosystems Food crops and products, perfumes, medicine Leaves are usually flat to maximize photosynthesis. Leaves have pores. True roots to hold down plant & take in nutrients.

16. Angiosperms 1.Male anther produces pollen grains (sperm) 2.Pollen grains from one flower is carried by wind or organisms (eg. Bird, insect) to another flower. Pollen grains travel down pollen tube to the ovary (female egg) 3.Sperm fertilizes the egg to form a zygote (embryo) within a seed 4.Seed can develop further within a fruit (ovary wall) 5.Seed can be released with or without the fruit and will develop into a new sporophyte plant

17. Male (bottom) and Female (top) Pine Cones

18. Gymnosperms 1.Male pollen cones produce microspores, which develop into pollen grains (sperm) 2.Pollen grains from a male cone is carried to the female seed cone by wind or an organism. 3.Sperm fertilizes the egg to form a zygote (embryo) within a seed 4.Zygote forms into a seed cone (female) 5.Seed (with wing) can be released and forms into a new sporophyte plant that will grow more.