1. Unit 7--Plants Chapter 25 Plant Responses & Adaptations

2. Plant Hormones Auxin = first discovered located in growing tips of roots/stems for stem elongation inhibits bud growth leaf & fruit drop

3. Plant Hormones Ethylene = for fruit ripening & drop or leaf & flower drop

4. Place fruits in a brown bag to trap ethylene gas release to speed up ripening

5. Plant Hormones Gibberellins = for seed germination, fruit development & stem elongation

6. Tropisms Growth response toward a stimulus Phototropism = toward light Ex: sunflower

7. Tropisms Gravitropism(or geotropism) toward earth’s center Ex: roots (positive) & stems (negative)

8. Tropisms Thigmotropism = toward a support or something “touched” Ex: tendrils on a climbing vine

9. Modified Leaves Cactus spines Tendrils Carnivorous plants

10. Specialized Plants Parasitic plants –Ex: mistletoe Epiphytes –Ex: orchids, ball moss

11. Classification by life span Annuals = –entire life cycle in one growing season Ex: tomato plant

12. Classification by life span Biennials –lives through two growing seasons, separated by dormancy Ex: cabbage & carrot

14. Classification by life span Perennials = –live many years and through many periods of dormancy –Ex: trees, shrubs –Also, bluebonnets