REPRODUCTION IN FLOWERING PLANTS

1. REPRODUCTION IN FLOWERING PLANTS Prepared by: Ms. Sawera Farrukh

2. Contents • Parts of a Flower • Structure and Functions • Pollination • Self and Cross Pollination • Fertilization • Sexual and Asexual Reproduction

3. Parts of a Flower

4. Parts of a Flower

5. Parts of a Flower

6. Parts of a Flower

7. Parts of a Flower

8. Pollination • Pollination is the transfer of pollen (containing the male gametes) from the anther of a flower to the stigma (receptive surface of the female part of the flower) of the same or a different flower of the same species. • Pollination is of two types. • In cross pollination, the pollen is transferred from one plant to another by a pollinator, such as an insect, or by the wind. • In self pollination, the plant’s stamen sheds pollen directly onto its own stigma.

9. Pollination

10. Self and Cross Pollination

11. Self and Cross Pollination

12. Self and Cross Pollination

13. Self and Cross Pollination

14. Fertilization in Plants

15. Fertilization in Plants • Fertilization, which is the union of male gamete and female gamete to form a zygote, that ends up in the making of an embryo encased in a seed. • After pollination, when a pollen grain lands on the stigma of a flower, it generates a tiny pollen tube tipped with sperm all the way down the style to the ovule inside the ovary. • The pollen tube deposits the sperm (male gamete) at the egg (female gamete) inside the ovule. • When they combine, the sexual union is complete and the egg is fertilized into a zygote.

16. Fertilization in Plants • The sperm and egg each contain half of the genetic material from each parent flower needed to form a new plant. • The zygote will develop into a plant seed, which contains a food store and an embryo that will later grow into a new plant. • The ovary itself develops into the fruit after fertilization • Many flowers, such as kiwifruit, have lots of ovules in their ovary, so their fruit contain many seeds.

17. Reproduction

18. Reproduction • Asexual reproduction involves only one organism, so it is the reproduction without sex. • The offspring produced is identical to the parent. • It allows beneficial combinations of characteristics to continue unchanged and eliminates the often vulnerable stages of early embryonic growth. • It can be of many types as: - Binary Fission - Sporulation - Budding - Vegetative plantation - Regeneration - Fragmentation -

19. Asexual Reproduction Binary Fission • In this form of reproduction, the parent cell divides to give rise to two daughter cells. • The daughter cells then each develop into individual parent cells and give rise to two more daughter cells each, and so on. • The offspring will be identical to the parent, but since mutation can occur, there might be slight differences. • Many plants and some single-cell organisms, like amoeba, bacteria, etc. reproduce asexually. 

20. Asexual Reproduction Budding • Budding is a common form of reproduction in some lower animals (e.g. hydra) and plants (e.g. yeasts), which cannot simply split in half. • It is when a small part of a plant or animal breaks off and then, while they are separated from their “parent", they start to grow until both the "parent" and the "offspring" are the same size and both are capable of budding again. • This may happen many more times.

21. Asexual Reproduction Regeneration • Regeneration is a specialized form of asexual reproduction; by regeneration some organisms (e.g., the starfish and the salamander) can replace an injured or lost part. • Many plants are capable of total regeneration—i.e., the formation of a whole individual from a single fragment such as a stem, root, leaf, or even a small slip from such an organ.

22. Asexual Reproduction Sporulation • Spore formation is another means of asexual reproduction among protozoa and many plants; especially Fungi (for e.g. mushrooms) produce spores, which may be asexual or sexual. • A spore is a reproductive cell that produces a new organism without fertilization. • The asexual spores have the genetic material inside, which allows them to make a whole new organism identical to its parent.

23. Sexual Reproduction • Organisms that reproduce sexually produce male and female gametes (sex cells) for reproduction. • In Sexual reproduction,offspring is made by the fusion a cell each from a male and a female. • When the two cells merge into one, they form a zygote which is the fertilized cell that will grow into an embryo. • Embryo can then develop into the baby organism. • All the offspring of two parents are not identical, except if they are developed from the same fertilized egg.

24. Sexual and Asexual Reproduction

25. Sexual and Asexual Reproduction

26. Sexual and Asexual Reproduction

27. References • http://andromeda.cavehill.uwi.edu/flower_structure_and_function.htm • http://www.diffen.com/difference/Cross_Pollination_vs_Self_Pollination • http://www.diffen.com/difference/Asexual_Reproduction_vs_Sexual_Reproduction • http://www.edinformatics.com/math_science/asexual_sexual_reproduction.htm • http://www.infoplease.com/encyclopedia/science/reproduction-asexual-reproduction.html • http://www.sciencelearn.org.nz/Contexts/Pollination/Science-Ideas-and-Concepts/Pollination-and-fertilisation • http://homeguides.sfgate.com/difference-between-pollination-fertilization-flowering-plants-74393.html