Biotechnology Bell Ringers for October 19 th , 2010

1. Biotechnology Bell Ringersfor October 19th, 2010 • How many organisms are required for asexual reproduction in plants? • What is the difference between rhizomes and runners? • What is cell and tissue culture?

2. Biotechnology Objectivesfor October 19th, 2010 • We will talk about sexual reproduction in plants • We will examine the life cycle of “Fast plants” • Time permitting, we will talk about some current events in Biotechnology

3. Sexual Reproduction inFlowering Plants

4. What is Sexual Reproduction? • Sexual reproduction in plants is when a new individual is produced by combining materials from two parents

5. Sexual Reproduction in Plants • In plants, a sperm moves towards an egg • Fertilization occurs when the egg and sperm nuclei unite to start development of the offspring • By repeated cell division, the fertilized egg grows from a single cell into a many-celled embryo that develops into a seed

6. Sexual Reproduction in Plants • All living things that reproduce sexually take some features from each parent • Next year’s flowers will resemble this year’s flowers because they inherit features from both of their parents

7. Sexual Reproduction in Plants • The flower is the structure that makes sexual reproduction in flowering plants possible • A wide variety exists in flower appearance, but the function of the flower parts is the same

8. The Parts of a Flower • Most flowers have four parts • Sepals • Petals • Stamens • Carpels

9. The Parts of a Flower • The sepal protects the bud until it opens

10. Parts of a Flower • The petals attract insects • Some plants have no petals

11. Parts of a Flower • The stamen contains the male part of the flower • It produces pollen

12. Parts of a Flower • The carpels (ovaries) grow into fruits which contain the seeds

13. Stamen (Male) • The stamen produces pollen, a yellow powdery substance • Pollen is produced in the top of the stamen, in a structure called the anther • When the pollen grains are fully grown, the anther splits open

14. Pistil (Female) • The top of the pistil is called the stigma • When a pollen grain reaches the pistil, it sticks to the surface of the stigma • The stigma produces sugar that is used by pollen to grow a pollen tube inside the style

15. Pistil (Female) • The pollen tube inside the style allows delivery of the sperm down to the ovary • The ovary (carpel) is the enlarged part of the pistil where the female sex cells (eggs) are produced • The eggs (ovules) are fertilized by sperm from the style

16. Pollination • The transfer of the pollen from anther to the stigma is called pollination • Flowering plants use the wind, insects, bats, birds, and mammals to transfer pollen

17. Fertilization • Pollen grains germinate on the stigma, growing down the style to reach an ovule • Fertilized ovules develop into seeds • The carpel enlarges to form the flesh of the fruit and to protect the ovary

18. Seed Dispersal • Seeds are dispersed in many different ways: • Wind • Explosion • Water • Animals • Birds • Scatter

19. Wind Dispersal

20. Explosion Dispersal

21. Water Dispersal

22. Animal Dispersal

23. Bird Dispersal