START: Water vapour diffuses out of the leaf via stomata, The water water vapour fills the air spaces in the spongy mesophyll, Water evaporates from the spongy mesophyll cells , Pressure in the leaf xylem drops as water exaporates (compared to the stem xylem), Water is "pulled" towards lower pressure in the leaf xylem from the stem xylem vessels, A chain of water molecules in the stem xylem is pulled upwards towards the leaf xylem, The chain of water molecules is held together by the force of "cohesion', The force of cohesion is an attraction "between" water molecules, There is a second force involved, This force is "adhesion" an attraction between water molecules and cellulose in the xylem vessels, Water moves from root cortex cells to the root xylem by osmsosis, The overall process of water moving from root to leaf is TRANSPIRATION PULL, FINISH: Transpiration pull is also known as Cohesion Tension theory.

HIS 10.03.01 Transpiration Pull

โดย
ฝัง

ลีดเดอร์บอร์ด

สไตล์ภาพ

ตัวเลือก

สลับแม่แบบ

คืนค่าการบันทึกอัตโนมัติ: ใช่ไหม