1. Asexual Reproduction Versus Sexual Reproduction
Asexual reproduction occurs when a portion of a plant develops into a separate new plant that is genetically identical to the original, or parent, plant.
Sexual reproduction occurs when a plant’s sperm combines with a plant’s egg. The resulting zygote can grow into a plant that is a genetic combination of its parents.
Lesson 3-1

2. Animals live their entire lives as diploid organisms
Animals live their entire lives as diploid organisms. But plants alternate between haploid and diploid lives called alternation of generations.
generations
Lesson 3-2

3. Alternation of Generations (cont.)
Meiosis produce haploid spores. Spores grow by mitosis to become the haploid generation of a plant.
Then haploid generation produce haploid sperm or egg. These fuse during fertilization to form a diploid zygote which become the diploid generation of a plant.
Spores
haploid
sperm
Eggs
zygote
diploid
Lesson 3-2

4. How Do Mosses Reproduce?
Plants
Non Vascular
Mosses
Vascular
Seedless (Spores)
Ferns
Seed
Non
Flowering
Gymnosperms
Angiosperms
Lesson 1-3

5. How Do Mosses Reproduce?
Mosses have large haploid generations and small diploid generations. It uses spores, not seeds.
Haploid
Diploid
Spores
Lesson 3-3

6. How Do Ferns Reproduce? Plants Non Vascular Mosses Vascular
Seedless (Spores)
Ferns
Seed
Non
Flowering
Gymnosperms
Angiosperms
Lesson 1-3

7. How Do Ferns Reproduce?
Ferns have large diploid generations and small haploid generations. It uses spores, not seeds.
Diploid
Haploid
Spores
Lesson 3-3

8. Reproduction in Seedless Plants (cont.)
How do seedless plants such as mosses and ferns reproduce?
Lesson 3-3

9. How do seed plants reproduce?
Seed plants have large diploid generations and small haploid generations. The haploid generation is protected within the diploid generation.
In seed plants, pollen produce sperm which fertilize an egg in an ovule during pollination.
Diploid
Haploid
Pollen
Ovule
pollination
Lesson 3-4

10. How do seed plants reproduce? (cont.)
After fertilization, a seed is produced. A seed consist of: an embryo, its food supply, and a protective covering.
Seed
embryo
food supply
protective covering
Lesson 3-4

11. How do seed plants reproduce? (cont.)
Non-flowering seed plants produce male and female cones.
Lesson 3-4

12. How do seed plants reproduce? (cont.)
Flowering seed plants produce flowers which have either/both male (stamen) and female (pistil) reproduction organs.
Lesson 3-4

13. How do seed plants reproduce? (cont.)
The male reproductive organ of a flower is the stamen.
Pollen grains form at the tip of the stamen in the anther.
Lesson 3-4

14. How do seed plants reproduce? (cont.)
The female reproductive organ of a flower is the pistil.
Pollen can land at the tip of the pistil, or stigma.
The ovary is at the base of the style. It contains one or more ovules.
Lesson 3-4

15. How do seed plants reproduce? (cont.)
The ovary, and sometimes other parts of the flower, will develop into a fruit that contains one or more seeds.
The seeds can grow into new, genetically related plants that produce flowers, and the cycle repeats.
Lesson 3-4

16. Lesson 3-4

17. Difference Between Spores, Pollen, Seeds
Chromosomes
Haploid
Diploid
Function
Produce haploid generation
Produce sperm
Produce diploid generation
Size
~0.001 cm
~0.01 cm
~0.1 to 30 cm
Transported
Water, air, gravity
Water, air, insects
Water, air, animals
Lesson 3-4