1. Kingdom Plantae Plant Morphology

2. Ancestor = Charophytes  member of the green algae
Plant Evolution
Ancestor = Charophytes  member of the green algae
Algae had to come first  build up of oxygen in atmosphere  led to formation of the ozone layer
Land plants = embrophytes – multicellular dependent embryonic stage

3. Evidence that supports this idea:
Homologous chloroplasts
Similarity in characteristics d/t common ancestry
Biochemical similarity
Similarities in cytokinesis
Sperm cell ultrastructure
Genetic relationships
Similar chlorophyll a & b
20 – 26% cellulose in walls
Cell plate formation is similar

4. Problems associated with movement to land
Desiccation
Gas exchange
Support of multicellular structures
Spore or seed dispersal
Reproduction
1.Avoid or tolerate dessication – had no roots nor vascular tissues
2. Occurred via diffusion through cell walls  water loss
 live in cool, damp places
3. Stay close to ground  poor competitors for light
4. Had to rely on wind currents
5. Transfer gametes  live in wet places (flagellated sperm cells)

5. Found in all land plants
Derived characteristic – found in some algae but not in charophytes

6. Alternation of generations
Two Generations:
Sporophyte stage
Diploid stage
Sporo = spore (n) plant
sporopollenin
Spores produced via meiosis
Sporangium  sporocytes (2n)
Sporangium: protection in land plants (not seen in algae)
Sporopollenin: prevent dessication & microbial attack

7. Alternation of generations con’t.
Two Generations:
2. Gametophyte
a. haploid stage
b. gameto = gamete plant
c. gametes produced via MITOSIS

8. Sporophyte dominates life cycle
Monocots
Dicots
Angiosperms ovary
Gymnosperms no ovary
seeds
Cryptogams spores
vascular
Bryophytes nonvascular
land
Sporophyte dominates life cycle

9. Dominant during first 100 miy during plant evolution
- Means they lack xylem & phloem ( the conducting tissues)

10. Gametangia = structures where gametes are produced
Bryophytes
Gametangia = structures where gametes are produced
Archegonia - egg cells
Antheridia – sperm cells
* Sporophyte cannot live independently
Multicellular organ  Act as protective jackets & prevent gametes from drying out
FIND ON GAMETOPHYTE OR SPOROPHYTE?
GAMETES PRODUCED VIA MEIOSIS OR MITOSIS

11. Moss plants – gametophyte & sporophyte generations
SMALL TEETH AT END OF CAPSULE  HELP DESSIMINATE SPORES

12. PAGE 581, FIGURE 29.8
SPOROPHYTE GETS NUTRITION FROM GAMETOPHYTE

13. The Liverworts (Hepatophyta) - Marchantia sp.

14. The Hornworts (Anthocerophyta)
Anthoceros sp.

15. Bryophytes con’t
Stomata
a. openings in leaves that allow for gas exchange

16. NORMALLY FOUND ON UNDERSIDE OF LEAF

18. Bryophytes con’t Cuticle (made of cutin) HELPS PREVENT DESSICATION
PROTECT AGAINST MICROBIAL PREDATORS

19. No fundamental difference between above and below ground parts
Bryophytes con’t.
No fundamental difference between above and below ground parts
- 2 cm tall
Still have a need for water
5. flagellated sperm
b. usually found in moist places

20. Vascular Plants - Tracheophytes
Dominant stage = sporophyte
Specialized organs
Stems
Leaves
- megaphyll
- microphyll
Sporophylls: specialized leaf to house meiosporangia
Many cone shaped
Homosporous & heterosporous
Roots
- rhizomes
Megaphyll – borad leaves with highly branched veins  more efficient at photosynthesizing
Microphyll – needle-like leaf with single vein
c. Modified leaves that bear sporangia
- homosporous: sporangium produces single type of spore that develops into a bisexual gametophyte (several seedless vascualrs)
- heterosporous: sprorangium prouduces megaspor or micorspore  male and female gametophytes respectively, egg and sperm (seeds & few seedless vasculars)

21. Vascular plants con’t.
Branching  increased sporangia
Some contain lignin
a. structural support
Vascular tissues
a. Xylem
b. phloem

23. Two types of growth – apical meristem a. Primary growth
Vascular plants con’t.
Two types of growth – apical meristem
a. Primary growth
b. Secondary growth
Sperm still flagellated
Maintained stomata & cuticle
Growth at tips of stems and roots
B. increase in girth

25. Vascular Plants - Tracheophytes
 plants w/ pipes
Broken up into two groups:
Reproduce by spores Cryptogams: crypto: hidden, gam: sex
Reproduce by seeds
Gymnosperms: naked seed plants (cones) Angiosperms: seed surrounded by ovary (flowers)

27. Innovations of the Cryptogams
Roots - uptake water, minerals, nutrients, and gases
Vascular tissue - xylem & phloem arranged in bundles
Division of labor - specialized tissues and organs
Lignin - infused in xylem  support against gravity
Hormones - regulate plant development

28. P: Lycophyta
C: Lycopodiopsida
(microphylls)

29. P: Lycophyta
C: Sellaginellopsida
Sellaginella – The resurrection plant
l.s. strobilus

30. P: Psilotophyta * stems only

31. P: Sphenophyta
Equisetum sp. - Horsetail
Aerial stem in c.s.

32. Equisetum gametophyte & sporophyte stages.

33. Equisteum strobilus (cone: compact group of meiosporangium-bearing structures). Left: whole mount and Right: cross section showing sporangiophore: stem-like structure bearing sporangium (container in which spores are borne).

34. P: Pterophyta – the ferns Gametophytes

35. Sori (cluster of meiosporangia) on the underside of sporophylls (specialized leaf that bears meiosporangia) aka fronds.

36. Sori in c.s.
Note – indusium: layer of tissue protecting meiosporangia filled with meiospores. Annulus (head portion of meiosporangia) also present.

37. Left: fern gametophyte (prothallium) with archegonia and antheridia
Left: fern gametophyte (prothallium) with archegonia and antheridia. Right: sporophyte growing out of gametophyte. Rhizoids present.

39. Vascular Seed Plants
Gymnosperms – naked seed plants
Angiosperms – flowering plants

40. Seed plant characteristics
Seeds
Reduced gametophytes – microscopic
- Gametophytes develop from spores retained in sporangia of parental sporophyte protects female gametophyte from environmental stresses
- Gametophyte obtains nutrients from sporophytes

41. Seed plant characteristics con’t.
Heterospory
Megasporangia: produce megaspores that give rise to female gametophytes
egg within ovule
Microsporangia: produce microspores that give rise to male gametophytes
sperm within pollen

42. Non-flagellated sperm
Seed plants con’t.
Non-flagellated sperm
pollen
Moved by water, wind, insects, and animals
Egg cells
a. Called ovules  located inside the ovary

44. Seed plants
Purpose of the seed:
A. means of dispersal
B. Survive unfavorable conditions
C. Stores food for embryo
D. Protection from predators

45. Seed plants con’t.
Characteristics Maintained:
-vascular tissue
-cuticles
-stomata

47. Gymnosperms
Needle-like leaves
Found in moderately cold & dry regions
Direct pollination  ovules NOT enclosed in ovaries

50. dioecious: seeds & pollen produced on different sporophytes
P: Cycadophyta
dioecious: seeds & pollen produced on different sporophytes
strobili: micro and megasporophylls
360 million years old
Two major groups
Gymnosperms – “naked seed” plants
Angiosperms – flowering plants

51. Phylum: Ginkgophyta Ginkgo biloba – single species in the phylum.
i. dioecious
ii. male pollen cone w/ 2 microsporangia (whole & l.s.)
iii. no seed cone  ovules on end of branches

52. Phylum: Gnetophyta Welwitschia – found in the deserts of Africa
i. dioecious

53. Ephedra pollen cone: note microsporangia (compound strobilus)
Phylum: Gnetophyta con’t.
pollen cone: note microsporangia (compound strobilus)
Ephedra
seed cone: will produce two seeds

54. Phylum:Coniferophyta

55. Conifer characteristics
largest group of gymnosperms (600 spp.)
most are evergreen, monoecious, trees or shrubs
needle or scale-like leaves
compound seed cones (ovules on cone scales)
Simple or clustered pollen cone

57. Needle-like leaves
Curled bracts
fasicle (group of needle-like leaves attached to a single shoot) bundled in a papery sheath

58. Angiosperms
Produce seeds and flowers
Petals  brightly colored to attract pollinators
Dominate the landscape

59. The anatomy of a flower

60. Flower anatomy con’t.

61. Angiosperms con’t.
Pollination
Pollen grain lands on stigma and germinates
Pollen tube grows down through style into ovary  releases sperm into ovules (egg cells)
Mature ovary = fruit
Mature ovule = seed

62. Pollination

63. Parallel vein net-like vein Fibrous root tap root
Monocots vs. Dicots
Mono Dicot
1 cotyledon 2 cotyledons
Parallel vein net-like vein
Fibrous root tap root
Flwr parts in 3 flwr parts in 4-5
Scattered bundles bundles in ring
(in the stem)