1. Tropisms To turn toward or away from a stimulus. Toward is positive Away is negative http://education-portal.com/academy/lesson/tropisms-phototropic-geotropic-and-thigmotropic-plant- growth.html http://www.youtube.com/watch?v=pCFstSMvAMI

2. Geotropism (Gravitropism)  Plant growth toward or away from Earth or (gravity).  Roots grow down for anchorage  http://www.youtube.com/watch?v=mYZXax8V_L0 http://www.youtube.com/watch?v=mYZXax8V_L0

3. Chemotropisms  Plant growth toward or away from chemicals.  Roots grow toward useful minerals and grow away from harmful minerals.

4. Phototropism  Plant growth toward or away from the light. phototropism experiment https://drive.google.com/a/g.dentonisd.org/file/d/0B1XNUrs2mu16dGdPVWJmNGNXO DQ/view https://www.youtube.com/watch?v=zctM_TWg5Ik HD: computer enhanced https://www.youtube.com/watch?v=g8mr0R3ibPU

5. Thermotropism  Plant response due to heat.

6. Thigmotropism  Plant growth and movement in response to touch.  Vines will use thigmotropism to grab on for support to carry out phototropism in search for light.  Mimosa plants respond to touch for protection.  http://www.youtube.com/watch?v=m2xKjA69jNM http://www.youtube.com/watch?v=m2xKjA69jNM  https://www.youtube.com/watch?v=hG2olNnCi4U https://www.youtube.com/watch?v=hG2olNnCi4U

7. Hydrotropism  Plant growth toward water.

8. Hydrotropism  Necessary for TURGOR PRESSURE – water pressure inside plant cells that allow the plant to stand tall.

9. Tropism review  https://www.youtube.com/watch?v=zctM _TWg5Ik https://www.youtube.com/watch?v=zctM _TWg5Ik  http://www.youtube.com/watch?v=eDA8 rmUP5ZM http://www.youtube.com/watch?v=eDA8 rmUP5ZM

10. Xylem http://study.com/academy/lesson/xylem-the-effect- of-transpiration-and-cohesion-on-function.html  https://www.youtube.com/watch?v=Ir9bm3fli90 https://www.youtube.com/watch?v=Ir9bm3fli90 Vessels in a plant that bring water and nutrients up the stem of a plant and to the leaves.