1. Plants... Eukaryotic Multicellular Cell walls Reproduction
Asexually
Sexual via spores or seeds
Photosynthetic (most are autotrophs)

2. Cellular components of plants
Cell wall made of cellulose
Nucleus containing DNA
Mitochondria
Vacuole
Chloroplasts

3. Plant Characteristics
They make their own food
Chloroplasts contain chlorophyll
Photosynthesis
6CO2 + 6H2O  C6H12O6 + 6O2

4. Chloroplasts:

5. What is a Cuticle? A waxy layer that coats the surface of plant parts.
Keeps plants from drying out.
Plants Have a Cuticle

6. Plant Characteristics
Plant Cells have Cell Walls

7. What is a Cell Wall? a plant cell is surrounded by a rigid cell wall
outside of the cell membrane
helps support and protect the plant

8. How did Plants Originate?
First plants lived in water
similar to today’s green algae
Links b/w algae and plants
Cell walls
Some multicellular
Chlorophyll used in photosynthesis
Reproductive cycles
One of the earliest fossil vascular plants was Cooksonia,

9. Land adaptations: How did plants evolve? Resistance to drying
Conserving water
Reproducing w/o water

10. Overview of the Plant Kingdom
Divided into 5 groups based on 4 derived characters:
Embryo formation
Water conducting tissues
Seeds
Flowers

11. Alternation of Generations
Plants reproduce w/ spores + sex cells
There are two stages in a plant’s life:
Sporophyte (diploid 2N stage)
Gametophyte (haploid N stage)
Alternating b/w both phases is called alternation of generations!

12. What is a Sporophyte? A plant in the spore producing stage of life.
Spores can grow directly into an adult plant

13. What is a Gametophyte?
The stage in a plant’s life where it produces male and female sex cells.

14. More on Gametophytes The stage in a plant’s life where it
produces male and female sex cells.
Male and female sex cells must join in order to grow into a new plant.
This is called Fertilization.

15. Alternation of Generations
Sporophyte (2N)
Undergoes meiosis => haploid spores
Spores become a gametophyte (N)
Gametophytes produce gametes (sperm and egg)
Fertilization creates zygote which becomes sporophyte and cycle starts over!

17. Alternation of Generations
Which generation of a plant is diploid? Haploid?
Why does it make sense that the sporophyte generation is diploid?
What does the sporophyte produce?
What process produces spores?
Are the spores diploid or haploid?
The sporophyte generation is diploid, the gametophyte generation is haploid.
Sporophytes form when 2 haploid gametes fuse.
Spores
Meiosis
Haploid

18. Trends in Plant Evolution
As plants evolved:
the size of the gametophyte became smaller, while the sporophyte became larger.

19. Seedless Plants – Chapter 22.2
Mosses and Liverworts
Ferns, Horsetails, and Club Mosses

20. Essential Questions What are the characteristics of green algae?
What factor limits the size of bryophytes?
How is vascular tissue important?

21. Green Algae First plants appeared on Earth 550 mya
Absorb nutrients from their surroundings

22. Plants can be divided into 2 groups

23. How are Plants Classified?
Nonvascular Plants (Bryophytes):
no pipes to transport water and nutrients
depend on diffusion and osmosis
small: mosses, liverworts, hornworts

24. Mosses and Liverworts Small Live on bark, rocks, and soil
No vascular system
Must live in places that are wet
No true roots, stems, or leaves

25. Mosses

26. Liverworts

27. Hornworts

28. Mosses and Liverworts Live together in large groups Waxy coating
Each moss has rhizoids (root-like structures)
Rhizoids help anchor the plant

29. Bryophyte Life Cycle

30. How are Plants Classified?
Vascular Plants (Tracheophytes)
Have tissues that deliver needed materials throughout a plant - called vascular tissues.
Can be almost any size.
Are divided into gymnosperms and angiosperms

31. Vascular Plants Tracheids – Cells that transports water
Lignin – Compound in cell walls that makes them rigid
Formation of vascular tissue
Xylem (water) – Made up of tracheids
Phloem (food)
True leaves, roots, and stems
Sporophyte generation dominate
Sperm with flagella

32. Seedless Vascular Plants
Ferns, Horsetails, and Club Mosses:
Grow tall
Have vascular systems

33. Ferns

34. Horsetails

35. Fern Life Cycle

36. Division: Pterophyta

37. Gymnosperms Angiosperms
Seed Plants – Chapter 22.3
Gymnosperms
Angiosperms

38. Adaptations to land…
Reproduce by cones or flowers
Pollination instead of water fertilization
Protection of developing embryos in seeds
The selective advantages of invading this new habitat…
Less competition for sunlight
Mineral-rich soil

39. Seed Plants Two groups of seed plants:
Gymnosperms
Angiosperms
Gymnosperms include the conifers and cycads
Seeds in cones
Angiosperms are the flowering plants
Seeds in flowers

40. Gymnosperms: Phylum Coniferophyta (conifers)
Female cones
Male cones
Well adapted to cold & dry summers
“naked seeds” (no fruit)
Two kinds of cones
Males produce pollen grains (male gametophyte)
Female produce ovules (produce female gametophyte)
Female Gametophyte – Seed Cone (Gametophyte develops in ovule)
Male Gametophyte– Pollen Cone

41. Pollen (Gymnosperms) Outer layer of pollen is impermeable
Winged for wind dispersal
Male gametophyte
Lots of pollen is produced, and randomly reaches receptive ovules within female cones.
Pollination is more likely and more random by this method. Why don’t we see many hybrids?

42. Gymnosperm seed development

43. Gymnosperm Life Cycle vascular diploid dominant Non-motile gametes
naked seeds
not water dependent
Figure: 28.6d
Caption:
These life cycles are presented in order, from earlier- to later-branching lineages.

44. Flowering Plants – Chapter 22.4
Flowers and Fruits
Angiosperm Diversity

45. Essential Questions
What are the key features of angiosperm reproduction?
How are different angiosperms conveniently categorized?

46. Evolution of Plants: From Algae to Angiosperms

47. Angiosperms (Enclosed Seed)
Most diverse and geographically widespread
Benefits to humans and other animals
Medicines, cosmetics, food, building materials, etc...
Fascinating examples of co-evolution with animal species

48. Flowers and Fruits Flower: Reproductive structure
Contain ovaries (surround and protect seeds)
Improved vascular system
Pollen in anthers
After pollination, the ovary develops into a fruit
Fruit
Protect seeds
Disperse seeds
Pollen in anthers results in the potential for diverse distribution of pollen.

49. Flower Structure

50. Flower to Fruit

51. anthers “swing” up to brush bee’s back.
Pollen Dissemination
Hummingbird
“floral tubes”
red flowers
Scotch Broom...
anthers “swing” up to brush bee’s back.
Baobab tree
night pollinator

52. Seed Dispersal
Wind
Rivers and Floods
Carried

53. Angiosperms vascular diploid dominant Non-motile gametes seeds
not water dependent
Angiosperms
Heterosporous - Producing two types of spores differing in size and sex.

54. Angiosperm Classification
Monocot and Dicot:
# of cotyledons (seed leaves)
within the seed of a plant
becomes 1st leaves of a seedling
one leaf are called monocots
two are dicots
Cotyledons of eudicots supply nutrients for seedlings, but the cotyledon of monocots acts as a transfer tissue, and the nutrients are derived from the endosperm before the true leaves begin photsynthesizing.

56. Angiosperm Diversity
Since flowering plants are so diverse, they are now also classified by:
# of seed leaves
Strength and composition of their stems
Woody – Thick cell walls (Trees, shrubs)
Herbaceous – No wood as they grow
Number of growing seasons
Annual – Die after 1st growing season
Biannual – Dies after 2nd year
Perennial – Continue to grow from year to year

57. Monocots and Dicots
Now determined by more than just their # of seed leaves

58. Monocot vs. Dicot: Root System
Monocots - Fibrous root system
i.e. Grasses, lilies, orchids, palm trees
Rice, wheat, corn
Dicots-
Primary root or main root grows straight down TAPROOT: Often fleshy and stores food.
Carrots, beets, turnips and radishes have taproots.

61. A. Preventing Water Loss
Cuticle: waxy coating that prevents tissues from drying out
Stomata-openings in the cuticle that allow gas exchange to take place and also regulate water loss

62. Prevent Desiccation? Desiccation= Drying Out
As plants evolved further away from water
needed to evolve a waterproof structure/coating (cuticle)

63. Stomata

64. B. Autotrophic
Leaf-organ that enables the plant to trap and absorb light energy

65. Leaf Layers via microscope

66. C. Stabilization and Nutrient Absorption
(Accomplished with roots and mycorrihizea)
Roots:
organ that is used to transport water and minerals
anchor plants and store food
Earliest roots are rhizoids

67. The Root Main function = absorb water Functional Part = root hair
Structure from outside in:
Epidermis with root hair= protection
Cortex=support/storage
Vascular Bundle: Phloem, Vascular Cambium*, Xylem
*Vascular Cam: growth of new vascular tissue

68. Root Structure

69. D. Transportation System
Stem- Transport of water, food, and
minerals
Support of plant
Storage of materials

70. Structures of the Stem Epidermis (bark or green)=protection
Cork cambium =new growth of bark/ epidermis
Cortex = thick layer, sometimes contains chloroplasts, mostly for support
Vascular Bundle = contain transport tissues towards the middle of the stem
Xylem = transports water and minerals (generally in the middle)

71. More Structures
Phloem = transports sugars to all cells, located outside the xylem
Vascular cambium = separates the X and P, contains new cells for vascular growth
Pith = central portion of stem of tree, for storage

72. E. Reproduce Without Water
Spores/Cones/Seed-protective coat
prevents a developing embryo from drying out
Pollen and seeds
can reproduce far away from water
Pollen = plant sperm
light weight and won’t dry out, carried via wind, water, animal, etc..