Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Stimuli and responses in plants


Published on

Published in: Technology, Business
  • Get Now to Download PDF Format ===
    Are you sure you want to  Yes  No
    Your message goes here

Stimuli and responses in plants

  1. 1. By : ILLANI BINTI IBRAHIM SCIENCE TEACHER MRSM TAWAU Stimuli and responses in Plants
  2. 2. <ul><li>? TROPISMS </li></ul>
  3. 3. <ul><li>The response of plants to a stimulus in a particular direction </li></ul>
  5. 5. <ul><li>-Growth movement shown by plants in response to LIGHT . </li></ul><ul><li>-Shoots grow towards light </li></ul><ul><li>->POSITIVE PHOTOTROPISM </li></ul><ul><li>-Roots grow away from light. </li></ul><ul><li>->NEGATIVE PHOTOTROPISM </li></ul>
  6. 6. <ul><li>-Growth movement shown by plants in response to GRAVITY . </li></ul><ul><li>-Roots always grow downwards - in the direction of gravity </li></ul><ul><li>->POSITIVE GEOTROPISM </li></ul><ul><li>-Shoots grow upwards away from gravity. ->NEGATIVE GEOTROPISM </li></ul>
  7. 7. <ul><li>-Growth movement shown by plant in response to WATER . </li></ul><ul><li>-Roots grow towards water.->POSITIVE HYDROTROPISM -Shoots grow away from water. -> NEGATIVE HYDROTROPISM </li></ul>
  8. 8. <ul><li>-Response by plants to TOUCH or contact with solid structure </li></ul><ul><li>-Climbing plants - have weak stems and tendrils to support their own weight such as cucumber and morning glory </li></ul><ul><li>-Ensures that these plants </li></ul><ul><li>can grow upwards </li></ul><ul><li>- towards the sunlight. </li></ul>
  9. 9. <ul><li>? NASTIC MOVEMENT </li></ul>
  10. 10. <ul><li>-The direction of responses do not depend on the direction of the stimuli. </li></ul><ul><li>-Plants responses to external stimuli from any direction -Example : </li></ul><ul><li>Mimosa plant Venus fly trap </li></ul>