Kingdom Plantae

1. Kingdom Plantae

2. Plants are: • multicellular • photosynthetic • adapted for living primarily on land • non-motile (motile means capable of motion)

3. Plant Cells Have: • walls composed of cellulose • chloroplasts with chlorophyll • starch for food storage

4. Example for the following slide: • The sporophyte is the majority of the plant we see. • The gametophyte is relatively small and isn’t seen a lot

5. Diversity of Plants • It is estimated that there are anywhere from 300 000 to 500 000 species of plants that have been classified. • There is such variety in form and habitat that it is difficult to provide an example of a "typical" plant. • Modern classification puts plants into two main groups: • Nonvascular plants • Vascular plants

6. These divisions are broad and divide the kingdom according to adaptations for living on land. • Vascular plants grow in the most terrestrial environments, ranging from rain forests to deserts. • Nonvascular plants are more restricted in habitat because they tend to be smaller and more dependent on moist conditions than vascular plants.

7. Evolution of Plants • Aquatic means living in water. • If the water is salt water like ocean water, then the term "marine" is used. • Organisms living in freshwater have different adaptations than those living in marine environments.

8. It is generally accepted that plants evolved from simpler, algae-like ancestors. • Green algae has the same kind of chlorophyll as plants. • Both have cellulose in their cell walls and both use starch for food storage.

9. Ancestral plants were aquatic, and living in water has its advantages. • Water prevents the plants from drying up and is readily available so there is no need for roots. • Being surrounded by water is also convenient for reproduction gametes to come into contact.

10. Some algae have a holdfast that anchors them so that currents don't carry them away. • Some algaes have floatation devices or bladders that causes them to float toward the surface to get more sunlight.

11. Adaptations for Living on Land • Getting enough water when it no longer lives in the water, plants typically have roots that reach sources of water below the surface of the soil. • Protective mechanisms to avoid drying up-terrestrial plants have a waxy coating called the cuticle. This allows the plant to reduce water loss as much as possible.

12. Strong stems and structures to hold the plant up against gravity-such stems are necessary without the buoyancy of water to hold the plant up. • Surfaces for diffusion that are moist enough, but protected in a way that does not dry out the plant. • Stomata are pores in the leaves that allow for the gases to enter or exit the interior of the leaf where diffusion can take place.

13. Getting water from restricted areas of intake to other parts of the plant body. Also, nutrients must be transported from sites of photosynthesis to other parts of the plant that do not do photosynthesize.

14. Terrestrial plants have adapted complicated reproductive structures. An aquatic organism has the advantage of water allowing reproduction to take place by flagellated sperm. Land plants need reproductive structures that allow reproduction in the absence of water.

15. Homework Assignment

16. Mosses and Ferns • Nonvascular plants are in phylum (or in botany, division) Bryophytes • The bryophyte group includes • Mosses • Liverworts • Hornworts • These are odd sounding names but "wort" is from old English, meaning herb or medicinal plant.

17. Mosses • Mosses do not have a vascular system. • Consequently, they need to live near water or in a moist environment – places like marshes, the floors of a forest, and bogs. • Mosses obtain water and dissolved minerals by diffusion.

18. Mosses live close to the ground and do not grow taller than 20 centimetres. • Most are between one and five cm in height. • They have to remain small so that no cell is far from the water source. • Although they do not have true roots, stems, or leaves, they do have similar structures. • These structures are made of cells that are almost all the same. (not differentiated)

19. Ferns • Vascular plants are in the phylum Tracheophyta. • The simplest groups of trachephytes include: • whisk ferns • club mosses • horsetails • true ferns

20. These groups are among the oldest known vascular plants with fossils going back 400 million years. • All of these vascular plants reproduce by spores. • We will use ferns as our example of this group.

21. Ferns have a true vascular system comprised of xylem and phloem tubes. • Through the tubes, water moves up from the roots and the products of photosynthesis move down from the leaves and stem. • Some ferns grow as tall as 15 metres in tropical climates, but ferns in cooler climates are much smaller. • The gametophyte generation of ferns is short-lived.

22. In vascular plants, the sporophyte is the dominant generation. • A fern sporophyte has an underground stem known as a rhizome. • Rhizomes can branch and grow rapidly. • Roots grow downward from the rhizome and large leaves called fronds grow upward

23. Fern Reproduction • On the underside of fronds, haploid spores are produced by meiosis in structures called sporangia. • A cluster of sporangia form a sorus, which appears as a row of small dots. • When the sori burst open, the spores are released into the air. • When they land on moist ground, each spore grows into a gametophyte, which at this stage is called a prothallus.

25. During this part of the life cycle, the gametophyte is very small. • It is between one and two centimetres in size and resembles the shape of a heart. • These gametophytes produce sperm and eggs, but on different structures. • The sperm are released and swim to the eggs to fertilize them. • This diploid zygote grows into a typical sporophyte as the gametophyte disintegrates.

26. Seed Plants • Seeds are reproductive bodies that contain embryonic plants and stored food covered with a protective coating. • Seed plants do not need water to reproduce.

27. Our discussion of plant reproduction focuses primarily on sexual reproduction. • It is important to note that most plants (including seed plants) are able to reproduce asexually through vegetative propagation. • That means that many plants can reproduce via runners from roots or new plants growing from cuttings (regeneration). • There are many horticultural techniques for the propagation of plants that are really forms of asexual plant reproduction.

28. All seed-producing plants are vascular plants. • They all show the sporophyte generation as dominant with a small, and often not visible gametophyte generation. • There are about 250 000 species of seed-bearing plants on Earth today.

29. Seed plants are divided into two broad groups. • The gymnosperms are a diverse group with exposed seeds. • An example is a pine tree. • The angiosperms are the flowering plants. • Their seeds are held in fruits.

30. Celery stalks are the stems of celery plants. • Celery stems have xylem tubes that are large and easy to see. Experiment Time!

31. Roots • Vascular plants have developed root systems that can be quite extensive. • Plants that live in extremely dry conditions have the most extensive root systems. • Roots anchor the plant to keep it upright in the face of the wind. • Roots are evolved to absorb water and minerals from the soil. • Water that is taken in at the roots can travel to the topmost leaves of the plant where it is needed for photosynthesis.

32. The purpose of the stems of vascular plants is to lift the leaves upward towards the sun. • Photosynthesis happens primarily in the leaves. • The food that is produced in the leaves is carried by other tubes, called phloem, to nourish cells in other parts of the plant or for storage. • The trunk of a tree is its stem. • The wood is old xylem tissue. • The actively growing area is not too far under the bark.

33. Adaptations to Keep Water in the Plants • Water loss from the leaves of plants is called transpiration. • Some plants can regulate water loss from leaves by regulating the size of openings called stomates, or pores, in the undersides of leaves. • Guard cells cause stomates to close when it is very hot to prevent the transpiration of water.

34. Some plants have leaves that are round and thin, such as the leaves (needles) of pine trees. • This shape lowers the surface-to-volume ratio of the leaf, and therefore decreases the rate of transpiration. • The leaves and stem have cuticles that also prevent water loss. • Plants that live in dry conditions usually have a thicker cuticle.

35. Kingdom Plantae

36. Plants are:

37. Plant Cells Have:

38. Example for the following slide: • The sporophyte is the majority of the plant we see. • The gametophyte is relatively small and isn’t seen a lot

39. Diversity of Plants • It is estimated that there are anywhere from ________ to ________ species of plants that have been classified. • There is such variety in form and habitat that it is difficult to provide an example of a "typical" plant. • Modern classification puts plants into two main groups:

40. These divisions are broad and divide the kingdom according to adaptations for living on land. • ___________________ plants grow in the most terrestrial environments, ranging from rain forests to deserts. • ___________________ plants are more restricted in habitat because they tend to be smaller and more dependent on moist conditions than vascular plants.

41. Evolution of Plants • Aquatic means … • If the water is salt water like ocean water, then the term "marine" is used. • Organisms living in freshwater have different adaptations than those living in marine environments.

42. It is generally accepted that plants evolved from simpler, algae-like ancestors. • Green algae has the same kind of chlorophyll as plants. • Both have cellulose in their cell walls and both use starch for food storage.

43. Ancestral plants were aquatic, and living in water has its advantages. • Water … • Being surrounded by water is also convenient for reproduction gametes to come into contact.

44. Some algae • Some algaes

45. Adaptations for Living on Land • Getting enough water • Protective mechanisms to avoid drying

46. Strong stems and structures to hold the plant up against gravity-such stems are necessary without the buoyancy of water to hold the plant up. • Surfaces for diffusion that are moist enough, but protected in a way that does not dry out the plant. • Stomata are.

47. Getting water from restricted areas of intake to other parts of the plant body. Also, nutrients must be transported from sites of photosynthesis to other parts of the plant that do not do photosynthesize. • Xylem • Phloem

48. Terrestrial plants have adapted complicated reproductive structures. • An aquatic organism has the advantage of water allowing reproduction to take place by flagellated sperm. • Land plants need reproductive structures that allow reproduction in the absence of water.

49. Homework Assignment

50. Mosses and Ferns • Nonvascular plants are in phylum (or in botany, division) ___________________ • The ___________________ group includes • These are odd sounding names but "wort" is from old English, meaning herb or medicinal plant.