1. PLANTS: REPRODUCTION, GROWTH & SUSTAINABILTY
SBI3U1

2. PLANT REPRODUCTION

3. Plants can reproduce both sexually and asexually

4. Sexual Vs. Asexual Reproduction
Sexual reproduction is by sporic reproduction (alternation of generations).
Haploid gametophyte cells (1n) produce gametes
Diploid sporophyte cells (2n) produce spores.
Male and female gametes unite to form the sporophyte that continues the life cycle.

5. OVERVIEW Copy chart on pg. 583 (textbook) Plant Reproduction Sexual
Seedless Plants
Non-vascular
Vascular
Seed Plants
Gymnosperms
Angiosperms
Asexual
Natural Vegetative Propagation
Artificial Propagation
OVERVIEW
Copy chart on pg. 583 (textbook)

7. Sexual Reproduction in Seedless Plants
-Fertilization -> the sperm swims from the male gametophyte to the egg in the female gametophyte.
-Water must be present & sperm must have a flagellum.

8. Sexual Reproduction in Seed Plants
Ex. gymnosperms and angiosperms
Male gametophytes called a microspore, develop into a pollen grain and sperm.
Female gametophyte, called a macrospore, develops into an egg cell.
In order for pollination
to occur; male gametophyte
must be transferred to the
female reproductive structure.

9. Angiosperms

10. 4 Basic Flower Organs sepals – protect the flower bud
petals – attract pollinators
stamens – male reproductive structure
pistils – female reproductive structure
The reproductive structures are in the flowers.
Fertilization & seed development occur within the ovule.
Pollination takes place on the stigma.
Female gametophytes develop in the ovules, where eggs are formed.

11. Variations Among Flowers
Complete flowers – Contain all four flower organs
Incomplete – Missing one or more flower organs
Grass flowers lack sepals and petals.
They are incomplete.

12. 4 Pollinating Mechanisms
Self-pollination: Plants pollinate themselves
Cross-pollination: Plants receive pollen from another plant.
Animal Pollination: Insects and other small animals move from flower to flower collecting nectar and moving pollen. Bright, sweet- smelling flowers attract these pollinators.
Wind Pollination: Wind carries pollen and it lands on a receptive reproductive organ.

13. Self Pollination vs. Cross Pollination

14. Label your diagram using handout

15. Seed & Fruit Development
Fertilization is one long process that ends with the formation of a seed.
A seed is part of a fruit, developed from the ovary

16. Monocot vs. Dicot Seeds
The outside layers of the ovule form a protective cover called the seed coat. Ex:Beans or peas have seed coats that can easily be peeled off

17. Seed germination A Seed may remain dormant
for a period of time and then
resumes growth

18. Asexual reproduction
Produces genetically- identical clones from a parent
Vegetative propagation – Involves growing a new individual from only a portion of the original plant

19. 8 Types of Vegetative Propagation
1.Division Splitting
2.Grafting

20. 8 Types of Vegetative Propagation
3. Leaf Cutting
4. Stem Cutting

21. 8 Types of Vegetative Propagation
5. Root Cutting
6 Simple Layering

22. 8 Types of Vegetative Propagation
7. Air Layering
8. Cell Culturing

23. PLANT GROWTH & DEVELOPMENT

24. Plant Hormones
Hormone: chemical compound produced in one part of the plant that controls growth in another part of that plant
act as chemical signals between cells and tissues
Some stimulate growth, others inhibit growth

25. 5 Main Plant Hormones:
Auxins
Cytokinins
Gibberellins
Ethylene
Abscisic acid

27. Stimulatory Hormones: 1.Auxins: Principal plant hormone
“to increase”
stimulates elongation of plant cells
Produced in developing leaves/seeds and shoot tips (apex)
Controls upward growth – apical dominance

28. Stimulatory Hormones: 2. Cytokinis
Promotes cell division & differentiation
Stimulates the production of proteins required for mitosis and cytokinesis
delays aging of leaves and fruit

29. Stimulatory Hormones: 3. Gibberellins
Stimulates taller, stronger plant growth
Stops dormancy in seeds
Used in commercial crops to increase fruit size or larger cluster size in grapes

30. Inhibitory Hormones: 4. Ethylene
Promotes ripening of fruit
Gaseous hormone
Diffuses through spaces in cells and transported within phloem

31. Inhibitory Hormones: 5. Abscisic Acid
Induces seed dormancy
Inhibits growth of buds in plant stems
Closes stomata & blocks intake of CO2

32. Plant Responses to Environmental Stimuli
UNIT 5
Chapter 14: Plants: Reproduction, Growth, and Sustainability
Section 14.2
Plant Responses to Environmental Stimuli
Nastic response: a movement of the plant that is reversible, repeatable, and does not include growth.
Ex: the opening & closing of flower petals as light conditions change.

33. Tropic Responses Phototropism Gravitropism Thigmotropism
Growth responses to external stimulation coming from one direction in the environment.
3 main Types:
Phototropism
Gravitropism
Thigmotropism

34. 1) Phototropism
a growth response to light produced by an unequal distribution of auxin.
More auxin on the side with less light causes those cells to elongate and bend the plant toward the light

35. 2) Gravitropism Growth response to gravity
a “positive” growth response of the roots downward or a “negative” growth response of stems upward

36. 3) Thigmotropism a growth response to mechanical stimuli
Contact with another object
Ie. Ivy growing on a fence or tree

37. Other Factors that Affect Plant Growth
Nutrients
Soil pH
Nutrients needed in large amounts are called macronutrients (ie.N, K, Ca, Mg)
Nutrients needed in small amounts are called micronutrients
( ie. Cl, Fe, B, Zn)
Optimal soil pH is slightly acidic ( pH 6-7) or slightly basic ( pH 7-8)
Any extremes in pH will inhibit normal plant growth