1. TRANSPORT IN PLANTS Gas exchange Photosynthesis Transpiration
Xylem – water &
mineral transport
Phloem –
sugar transport
Gas exchange –
cellular respiration
Water & mineral
absorption

2. WATER RELATIONS
IN PLANT CELLS

3. 3 MAIN CELL
COMPARTMENTS
TISSUE COMPARTMENTS
Symplast – travel via cytosol continum
Apoplast- travel via cell walls
& extracellular spaces

4. ABSORPTION OF WATER
& MINERALS BY ROOTS
Mycorrhizae –
Symbiotic relationship
Surface area for absorption

5. TRANSPORT OF WATER Root pressure Guttation Transpirational pull
Cohesion & adhesion

6. TRANSPIRATIONAL PULL

7. ASCENT OF WATER SOLAR POWERED HYDROGEN BONDING CHARACTERISTICS

8. CONTROL OF TRANSPIRATION
Photosynthesis – transpiration compromise
Stoma
open
Guard cells
Stoma
closed

9. Guard cells: inner walls thicker, cellulose microfibrils

10. Guard cells: regulated by uptake and loss of K+

11. Adaptations to reduce transpiration: thick cuticle, recessed stomata
XEROPHYTES
Stoma

12. TRANSLOCATION OF PHLOEM SAP
From source (sugar production) to sink (consumes or stores sugar), pressure flow hypothesis
Chemiosmotic mechanism for
active transport of sucrose

13. PRESSURE FLOW Loading of sugar reduces water potential
Absorption of water generates pressure and forces flow
Pressure gradient reinforced
by the unloading of sugar at the sink
Xylem recycles water
from sink to source

14. Tapping phloem-sap with the help of an aphid

15. PLANT NUTRITION

16. THE AVAILABILITY OF SOIL WATER & MINERALS
Roots hairs increase surface area
Minerals actively transported in, water follows by osmosis

17. Soil Bacteria: Nitrogen fixing & Ammonifying (decomposers)

18. Development of a soybean root nodule Root nodules on legumes
Pericycle layer gives rise
to secondary roots
Root nodules
on legumes

19. MYCORRHIZAE

20. PARASITIC PLANT
CARNIVOROUS PLANTS

21. PLANT
REPRODUCTION

22. ANGIOSPERM LIFE CYCLE sporophyte/gametophyte; diploid/haploid

23. FLOWER ANATOMY Complete-all organs Incomplete-lacking 1 or more organs
Bisexual – both stamens & carpels
Unisexual-one or the other
Monoecious-carpellate & staminate flowers
Dioecious-separate plants

24. FLORAL
DIVERSITY

25. Angiosperm Gametophytes
Pollen grains
male
female

26. Reduce self - fertilization

27. Genetic Basis of Self-Incompatibility

29. Growth of
pollen tube and
double fertilization * *

30. Development of a Dicot Embryo

31. Development 0f a pea fruit Above cotyledons Below cotyledons
Embryonic root
Development
0f a pea fruit
Unique to monocots

32. GERMINATION Imbibition Release of Gibberellic acid
Aleurone  enzymes (α amylase)
Hydrolysis of endosperm

33. Seed Germination Radicle emerges 1st Cotyledons pulled from soil
Hypocotyl emerges, cotyledons
remain in ground
Shoot grows up through coleoptile

34. ASEXUAL REPRODUCTION (vegetative reproduction)
Fragmentation – separation of a parent plant into
parts that reform whole plants
Root system of a single parent gives rise to many adventitious shoots
Vegetative Propagation
- cuttings

35. PLANT RESPONSES TO EXTERNAL SIGNALS
Light induced greening of
dark sprouted potatoes
Grass seedling
growing toward
light

36. Signal Transduction Pathway (review)

37. TROPISMS Phototropism – response to light
Stems (positive); Roots (negative)
Gravitropism – response to gravity
Stems (negative); Roots (positive)
Thigmotropism – response to contact
Curling around objects (vines)

38. PHOTOTROPISM

39. WENT EXPERIMENTS CONCLUSION CHEMICAL SIGNAL PRESENT IN COLEOPTILE
TIP STIMULATES GROWTH
AS IT PASSED DOWN THE
COLEOPTILE
HIGHER CONCENTRATION
OF CHEMICAL ON DARKER
SIDE CAUSED THE PLANT
GROWTH TO CURVE TOWARD
LIGHT
- NAMED THE CHEMICAL “AUXIN”

40. PLANT HORMONES Auxins – stem elongation in apical meristems
Fruit maturation, prevents abscission
Cytokinins – cell division in roots, embryos, fruits
Gibberellins – stem elongation in mature regions, fruit development
Abscisic acid – dormancy, stress, abscission
Ethylene – fruit ripening

41. Apical Dominance:
Terminal shoot inhibits lateral buds
Auxin responsible

42. Gibberellins:
Stimulate growth (elongation & division)
Tall spindly plants
Larger seedless grapes

43. Abscisic Acid (ABA)
Seed dormancy
-Inhibits germination
Stress
Drought
Winter

46. Leaf Abscisision
Parenchyma cells
w/ very thin walls
Change in balance
of auxin & ethylene
Aging leaf produces
less & less auxin

48. Phytochrome regulation of lettuce seeds
Pr ↔ Pfr acts as a switching mechanism
that controls various light-induced events

49. Functions as the
photoreceptor
Links light reception
to cellular responses

50. bluish
blue-greenish
Switched on by

51. Photoperiodic Control of Flowering
Short day plants flower
when night exceeds the
critical dark period
Long day plants flower
when night is shorter than
the critical dark period

53. FLOWERING
HORMONE?

54. Root Gravitropism

55. Smaller plant touched 2x/day
Rapid turgor movements

56. Response to flooding & oxygen deprivation