Chapter 20 Classifying Plants

1. Chapter 20Classifying Plants Objective: explain difference between vascular and nonvascular plants and plants with and without seeds. And describe parts of the plants.

2. Questions you should be able to answer by the end of the lesson. • What are 3 main groups of plants? • Who developed the classification system of organisms that is used today? • What are the 2 ways that vascular tissue is important? • What are other names for flowering plants and nonflowering seed plants? • What’s the largest group of seedless vascular plants? • Why are the seeds of gymnosperms called “naked seeds?” • Why are conifers able to live where other plants cannot? • What group of plants do not have seeds? • Why are there more seed plants than seedless plants? • Where do mosses need to live and why?

3. How are plants alike and different? • Flowers • Needles • Green leaves • Different shapes and sizes • Make own food • Carry water • Produce O2 • Reproduce

4. How Plants are Classified • Most plants live in tropical rain forests. • Divided into groups to make them easier to study: • Body parts (seeds), tubes, roots, stems, and leaves • 3 main groups: • seed plants • ferns • mosses

5. History of Classification • Started 2000 years ago. • Greek Philosopher Aristotle first classified plants and animals. • In 1753- Carolus Linnaeus developed a new method that we use today. • Organisms have 2 word names (genus and species) called scientific name • All maple trees start with Acer • Sugar maple- Acer saccharum • Red maple- Acer rubrum

6. Vascular • Seed plants and ferns • Have tubelike cells- vessels or tubes called vascular tissue • The tissue forms tubes that transports food and water through the plant • Have well developed leaves, stems, and roots

7. Vascular • Vascular tissue is important: • allows food and water to be transported through the plant= the plant grow larger because leaves and stems do not need to be near water. • Vascular tissue is thick and provides support for a plant. Also allows plants to grow tall.

8. Nonvascular Plants • Mosses • No tubelike cells • Short and must have contact with moisture • No tubes to support them so stay small • Grow in damp shady places on the ground and on sides of trees and rocks. • Don’t have true leaves, stems, or roots

9. Seed Plants • Use seeds to reproduce • A seed is a plant part that contains a beginning plant (called an embryo) and stored food. • The seed has a seed coat that holds in moisture. When the conditions are right, the embryo grows into a full- sized plant.

10. Seed Plants • Have the most advanced vascular tissue of all plants. • Well developed leaves, stems, and roots. • Different sizes and shapes (from 1mm- 379 ft)

11. Seed Plants (Flowering) • Different sizes and shapes help them live in different places. • Grasses, trees, flowers, bushes, vines, and cacti. • Most are angiosperms, or flowering plants. • Fruit protects the seed- forms from part of the flower. • Flowers come in many shapes and colors.

12. Seed Plants (Nonflowering) • Gymnosperms (nonflowering) • Not surrounded by fruit • Seeds produced inside cones

13. Seed Plants (Nonflowering) • Over 700 species of gymnosperms • Conifers (600 species) • Ginkgo Trees

14. Seed Plants (Nonflowering-Conifer) • Major group is conifers – 600 species (woody shrubs or treed) • Make up 30% of forests • Pines, spruces, firs, junipers, and yews • Leaves are shaped like needles and are green all year (called evergreens) • Needles do not lose water easily like big leaves • Easier to live in dry places where trees must store water for a long time

15. Seed Plant (Nonflowering-Ginkgo) • Gingko is other most familiar nonflowering tree • Used in city streets because they are able to survive pollution better than other trees

16. Seedless Plants • 2 types • Largest: ferns and related plants • Vascular (like seed plants) • No seeds (unlike seed plants) • Mosses and related plants • nonvascular

17. Seedless Plants (Fern) • Over 10,000 species of Ferns • Many are tropical • From tiny to large treelike size • Have well developed leaves, stems, and roots

18. Seedless Plants (Fern) • Leaves (or Fronds) are usually large and flat • Divided into small sections, or leaflets that spread out from a center rib • If look closely, you can see new fronds that are curled up, as they uncurl they grow.

19. Seedless Plants (Fern) • On the underside of the frond, you can see small dots called sori- are clusters that contain the reproductive cells of ferns- called spores. • When the spores are ripe, the sori burst and open and release the spores into the air

20. Seedless Plants (Fern) • The rhizome is a plant part that has shoots aboveground and roots belowground

21. Seedless Plants (Fern) • After they are released, spores must land in a moist place to produce a tiny plant. • Must have consistent moisture to grow • Seeds usually survive longer than spores when conditions are dry. • Where do you think ferns live? Why are there more seed plants than seedless plants?

22. Seedless Plants (Moss) • Moss is nonvascular- no vascular tissue to transport water • Must live in moist, shady places • Where will you find moss growing? • Simple leaflike and stemlike parts • More than 9,000 species • No well developed leaf, stem, and roots

23. Seedless Plants (Moss) • Get water through root like threads called rhizoids • Grow in woodlands and sides of streams • Look like little trees and often form carpetlike mats on the forest floor.

24. Seedless Plants (Moss) • Like Ferns, mosses reproduce by spores • Mosses produce great numbers of sores.

25. Objective Recap: • What are 3 main groups of plants? • Who developed the classification system of organisms that is used today? • What are the 2 ways that vascular tissue is important? • What are other names for flowering plants and nonflowering seed plants? • What’s the largest group of seedless vascular plants? • Why are the seeds of gymnosperms called “naked seeds?” • Why are conifers able to live where other plants cannot? • What group of plants do not have seeds? • Why are there more seed plants than seedless plants? • Where do mosses need to live and why?

26. Lesson 2- The Vascular System in Plants Objectives: • Identify the main parts of the plant. • Describe the structure and function of roots, stems, and leaves.

27. Questions you will be able to answer by the end of the lesson: • What are the functions of roots? • What is the difference between xylem and phloem tissue? • How are annual growth rings made? • What are the main parts of a leaf?What do stomata do?

28. The Vascular System in Plants • Tiny tubes that run through roots, leaves, and stems of most plants. • Connects to all parts of the plant • To make food and survive- roots take water and minerals from the soil • Leaves collect energy form the sun and CO2 from the air

29. What Roots Do • Hold plant firmly in ground. • Absorb water and minerals from the soil • Store water and minerals and food made in leaves. • Vascular system brings water and minerals to other parts of the plant

30. The Parts of a Root • The tip of the root is always growingthrough millions of tiny root hairs • Root hairs: • absorb water and minerals from the soil • store the water and minerals until needed. Can also store food from leaves carried by the phloem.

31. The Parts of a Root • Xylem- vascular tissue that carries water and minerals from roots to leaves • Leaves use water and minerals to make food. • Phloem- vascular tissue carry food from leaves to stems and roots

32. What Stems Do • Stems connect leaves with roots • Most are above ground • Have 3 functions: • Support the leaves. Hold leaves us to receive sunlight. • Transport food, water, and minerals through the plant. • Store food.

33. The Parts of a Stem • Contain xylem and phloem • Contain special layer of growth tissue • produces new layers of xylem and phloem cells. • Layers build up in some plants so stems become thicker as they get taller. • In trees, these layers become wood. • In a tree trunk, one layer forms a new ring each year, called annual growth rings- tell tree’s age.

34. What Leaves Do • Trap sunlight • Have 4 functions: • Make food. • Store food. • Transport food to stem • Allow gases to enter and leave the plant • What gases enter and leave plants?

35. The Parts of a Leaf • Have 3 main parts: • Petiole- or stalk- attaches the leaf to a branch or stem • Blade – main part of the leaf- collects light from sun to make food • Veins- part of vascular system- think tubes arranged in a pattern- run through the blade, petiole, and stem- transport food and water between the stem and leaf.

36. The Parts of a Leaf • Underside has many small openings called stomata. • Each opening is called stoma. • Stomata allow gases to enter and leave the leaf. • Water vapor also leaves through stomata.

37. Objective Recap: • What are the functions of roots? • What is the difference between xylem and phloem tissue? • How are annual growth rings made? • What are the main parts of a leaf? • What do stomata do?

38. Lesson 3- How Plants Make Food Objectives: • Explain how and where plants make food. • Compute the chemical equation for photosynthesis. • Identify the importance of O2 in living things.

39. Questions you should be able to answer at the end of the lesson. • What is photosynthesis and where does it occur? • What is the source of the chemical energy stored in plants? • Why do living things need oxygen? • How is respiration the opposite of photosynthesis? • What do guard cells do?

40. Do Now • How do all plants make food? • Why are plants so important to humans?

41. The Process of Photosynthesis • During Photosynthesis, plants use the energy from the sunlight to turn CO2 and water into simple sugars (food) and O2 • How do plants get the CO2, H2O, and energy for photosynthesis?

42. The Process of Photosynthesis • Chloroplast- • organelles in plant cells where photosynthesis takes place. • Contain green pigment called chlorophyll- a pigment is a chemical that absorbs certain types of light. The cells of the green parts of the plants, such as leaves, contain many chloroplasts. • When sunlight hits the chloroplasts in the leaves, the chlorophyll absorbs light. • The sunlight then supplies the energy for photosynthesis

43. The Process of Photosynthesis • Plants use the sun energy to split H2O • The Oxygen leaves through the stomata and goes into the air. • The Hydrogen combines with the CO2 to make sugar • Plants store the energy of sunlight and the sugar as chemical energy.

44. Chemical Energy • Chemical energy –stored in the bonds of molecules • When chemicals break apart, energy is released • Glucose is the simple sugar that plants make during photosynthesis. • Contains stored chemical energy • Animals that eat plants use the stored energy

45. The Chemical Equation for Photosynthesis • 6CO2 + 6H2O + light energy C6H12O6 + 6O2 http://www.teachertube.com/viewVideo.php?video_id=49549 http://www.teachertube.com/viewVideo.php?video_id=62625&title=Photosynthesis

46. The Importance of Oxygen • Oxygen is used to break down food to release the energy- called cellular respiration • Photosynthesis is only in plants • Cellular respiration happens in plants and animals • You get your energy when you break down the glucose from the food you eat. • During cellular respiration- O2 combines with Hydrogen to make water and CO2 is released as a waste product (opposite of photosynthesis)

47. Cellular Respiration

48. What does each formula represent? Which way does the arrow for cellular respiration and photosynthesis go? 6CO2+ 6H2O C6H12O+ 6O2

49. CO2-O2 cycle

50. Producing Oxygen • O2 is made from the H2O in plants • Plants use H2O to also make sugars (+ CO2) • O2 forms into O2 gas and some is released and some is used for cellular respiration