1. Introduction to Plant Reproduction
23.1

2. Reproduction Sexual reproduction Joining of an egg and sperm
Asexual reproduction
A single organism replicating its genetic material to split into two identical organisms.

3. Vegitative Reproduction
A form of asexual reproduction where a new plant grows from parts of an existing plant.
Fast reproduction
Examples:
Strawberry runners
Moss fragmentation
Potato eyes and buds

4. Alteration of Generations

5. Alteration of Generations Of Nonseed Nonvascular Plants

6. Alteration of Generations Of Nonseed Vascular Plants

7. Alteration of Generations Of Naked Seed Vascular Plants

8. Alteration of Generations Of Flowering Seed Vascular Plants

9. Alteration of Generations
Fertilization:
Nonvascular plants- Need a film of water for the sperm to reach the egg.
Vascular plants- Do not need water for the sperm to reach the egg.

10. Alteration of Generations
As plants evolved, the sporophyte generation became larger:
Nonvascular plants- Sporophyte depends on the gametophyte for support and nutrition.
Vascular plants- Sporophyte lives independent of the gametophyte.

11. Moss reproductive cycle
Gametophyte dominant
Male= Antheridium
Female= Archegonium
Antheridium
Archegonium

12. Moss reproductive cycle
Antheridium- Male produces flagellated sperm that need water to get to the archegonium.
Chemotaxis- Female archegonium produces chemicals that attract/direct the sperm.

13. Moss reproductive cycle

14. Moss reproductive cycle
Sporophyte- Depends on the gametophyte for support and
nutrition.
Protonema- Spores that land in a favorable spot develop into a protonema (gametophyte
generation).

15. Fern reproductive cycle
Sporophyte dominant
Frond- feathery stems of a fern
Sorus- underneath the frond
Produces spores

16. Fern reproductive cycle
Prothallus
The fern spore grows into a prothallus when it lands on damp, rich soil.
Heart shaped
Contains Antheridia
& Archegonium

18. Conifer reproductive cycle
Sporophyte dominant
Heterosporous- Produces two kinds
of spores that develop into male and female cones.
Female cones
Made of many scales
2 ovules at the base of each scale
Each ovule produces a Megaspore which develops into the female archegonia.

19. Conifer reproductive cycle
Male cones
Made of small scales that form microspores
4 microspores develop into a single pollen grain
Pollen grains are the
male gametophyte that
are transported on air
currents

21. Chapter 23.2
Flowers

22. The Parts of a Flower Most flowers have four parts: sepals, petals,
stamens,
Carpels
(pistils)

23. The parts of a flower Sepals protect the bud until it opens.
Petals attract insects.
Stamens make pollen.
Pistils (carpel) grow into fruits which contain the seeds.

25. Stamen (male) Anther: pollen grains grow in the anther.
When the grains are fully grown, the anther splits open.
Filament: holds the anther

26. Pistil (female) Stigma – sticky place for pollen to attach
Style
Ovary
Stigma – sticky place for pollen to attach
Style – where pollen nuclei travels to reach the egg
Ovary – where egg is located

27. Modifications in Flowers
Complete flowers – have all four organs (sepals, petals, stamens, and pistils)
M orning glory and tiger lily
Incomplete flowers – lacks one or more of the four organs
Squash and corn

28. Tiger Lily – a complete flower

29. Incomplete Flowers
Female Squash Flower
Male Squash Flower

30. Modifications in Flowers
P erfect flowers- Have both stamens and pistils (E x: Lily)
Imperfect flowers- E ither have a functioning stamen or pistil, but not both
E x : Cucumber, Squash

31. Pollination Mechanisms
Animal pollination
hummingbirds & bees transfer pollen from plant to plant
Flowers are brightly colored or highly scented
Wind pollination
lightweight and are carried by wind
Small flowers with little color or scent
Self pollination
Able to pollinate flowers on same plant
Have both pistel and stamen

32. Pollinators

33. PHOTOPERIODICITY
Plants flower based on the number of hours of darkness they are exposed to
Short-day plants -
flower when days are short (fall, winter, spring)
Ex: Pansy,
Poinsettias

34. PHOTOPERIODICITY Long-day plants -flower when days are long (summer)
Examples:
Potatoes
Clover
Spinach

35. PHOTOPERIODICITY
Intermediate-day plants- Grow when darkness is about equal to daylight.
E x : Sugar Cane

36. PHOTOPERIODICITY
Day-neutral plants- Hours of darkness does not effect flowering, as long as there is enough daylight to perform photosynthesis.
E x: Corn, tomatoes, cotton, roses

37. Chapter 23.3
Flowering P lants

38. Flowering Plant reproductive cycle
Sporophyte dominant
Ovary- produces 4 megaspores, but 3 disintegrate and only one remains.
Double fertilization – requires 2 sperm to fertilize the egg and make a seed.
Seed – embryo (cotyledons), endosperm (food for embryo), seed coat (protect seed)

39. Flowering Plant Reproduction

40. 4 kinds of fruit 1. Simple Fleshy fruits- contain one or more seeds.
Ex: Apples, Peach, grape, tomato, pumpkin

41. 4 Kinds of fruit
2. Aggregate fruit- Most berries. Many female parts fuse to form one fruit.
Ex: Blackberries, strawberries, raspberries

42. 4 Kinds of fruit 3. Multiple fruit- Flowers fuse to form one fruit.
Ex: Pineapples, figs

43. 4 Kinds of fruit 4.. Dry fruit- Fruits that are dry.
Ex: Nuts, grains, seed pods

44. Seed Dispersal Water Wind Animals Coconuts Dandelions
Fruits attract animals that will eat the seeds so that the seeds can be carried far away where it won’t have to compete with its parent.

45. Seed Germination Requires: Water (swells and breaks seed coat)
Oxygen (cell respiration as seed grows)
Optimal Temperature (each plant requires a certain temperature to begin growth)
Seeds will lie dormant in their hard seed coats waiting for optimal conditions.