1. 3-2 Notes – Plant Reproduction
Chapter 3
Lesson 2

2. Alternation of Generation
“Alternation of generations” describes the life cycle of organisms, such as plants, that alternate between diploid stages and haploid stages.

4. Alternation of Generation
In seedless plants, the haploid generation lives on its own.
In seed plants, the haploid generation lives inside diploid tissue.

5. Seedless Plant Reproduction
Examples: mosses and ferns
They grow from haploid spores, not seeds
Spores grow by mitosis and cell division to form haploid plants.

6. Seedless Plant Reproduction
Fertilization results in a diploid zygote that grows by mitosis and cell division into the tiny diploid generation.

8. Seed Plant Reproduction
Most plants are seed plants.

9. Seed Plant Reproduction
Sperm cells form inside a protective structure called a pollen grain.

10. Seed Plant Reproduction
Egg cells form inside a female reproductive structure called an ovary.

11. Seed Plant Reproduction
In pollination, pollen grains from the male structure reach the female structure.

12. Seed Plant Reproduction
When sperm enters the ovule, fertilization occurs, and a seed develops.

13. Seed Plant Reproduction

14. Seed Plant Reproduction
A seed consists of:
an embryo, food supply, protective covering

15. Seed Plant Reproduction

16. Seed Plant Reproduction

17. Gymnosperms (Flowerless Seed Plants)
Gymno- means naked, so these seeds don’t have a fruit covering.

18. Gymnosperms (Flowerless Seed Plants)
Male cones produce pollen grains, and female cones produce eggs.
Seeds form as part of the female cone.
Female
Male

19. Angiosperms (Flowering Seed Plants)
Angio- means vessel, so these seeds do have a fruit covering.

20. Angiosperms (Flowering Seed Plants)
The flower’s male reproductive organ is the stamen.
The flower’s female reproductive organ is the pistil.

21. Angiosperms (Flowering Seed Plants)
Pollen grains form in the anther at the stamen’s tip.
The filament is a long stalk that connects the anther to the base of the flower.

22. Angiosperms (Flowering Seed Plants)
The pollen grains land on the pistil’s stigma, which is at the top of a long tube called the style.

23. Angiosperms (Flowering Seed Plants)
A pollen tube grows from the pollen grain into the stigma, down the style, to the ovary, where fertilization occurs.

24. Angiosperms (Flowering Seed Plants)
Each ovule and its embryo will become a seed.
The fruit of the plant protects the seed and helps with seed dispersal.

25. Angiosperms (Flowering Seed Plants)

27. 3.2 Plant Reproduction A B C D
In alternation of generations, the haploid structures of the diploid generation produces daughter cells called what?
A zygotes
B spores
C pollen
D seeds

28. 3.2 Plant Reproduction A B C D
What is an immature diploid plant that develops from the zygote of a seed plant called?
A embryo
B seed
C fruit
D stigma

29. What is another name for a flowering seed plant? A zygote B conifer
3.2 Plant Reproduction A B C D
What is another name for a flowering seed plant?
A zygote
B conifer
C gymnosperm
D angiosperm

30. Where are pollen grains formed? A anther B ovule C testes
D pollen tube

31. What flower structure becomes fruit surrounding the seed? A stamen
SCI 2.a A B C D
What flower structure becomes fruit surrounding the seed?
A stamen
B pollen tube
C ovary
D pistil

32. What type of seed plant does not produce flowers? A seedless plants
SCI 2.a A B C D
What type of seed plant does not produce flowers?
A seedless plants
B gymnosperms
C angiosperms
D strawberry plants