transport in plant theories

1. Which theory suggests that water is forced upwards in plants due to osmotic pressure in root tissues?

• a. Capillarity theory
  

• b. Root pressure theory
  

• c. Imbibition theory

• d. Transpiration pull theory

  
  

2. What is a major defect of the root pressure theory?

• a. It can only explain water ascent in short plants
  

• b. It cannot explain water ascent in gymnosperm plants
  

• c. It allows water to rise more than 100 meters
  

• d. It is not affected by external factors

  
  

3. According to the imbibition theory, what allows xylem walls to imbibe water?

• a. Lignin and cellulose
  

• b. Osmotic pressure
  

• c. Cohesive force
  

• d. Transpiration pull

  
  

4. Why is capillarity considered to have a weak effect in sap ascent?

• a. It relies on large tubes
  

• b. It doesn't work in gymnosperms
  

• c. The finest capillary tube doesn't allow rise more than 150 cm
  

• d. It requires high temperatures

  
  

5. Which forces are part of the transpiration pull, cohesion, and adhesion theory?

• a. Osmotic, adhesive, cohesive
  

• b. Cohesive, adhesive, transpiration pull
  

• c. Capillary, osmotic, cohesive
  

• d. Transpiration push, cohesive, adhesive

  
  

6. What is the role of adhesive force in the transpiration pull theory?

• a. It breaks the water column
  

• b. It attracts water molecules to each other
  

• c. It helps hold the water column against gravity
  

• d. It lowers the water concentration in the stomata

  
  

7. What causes the break of cohesion in a water column during transpiration?

• a. Excessive water intake
  

• b. Formation of air bubbles
  

• c. Strong cohesive forces
  

• d. High root pressure

  
  

8. What is the main role of phloem in plant transport?

• a. Transport water from roots to leaves
  

• b. Translocate organic substances throughout the plant
  

• c. Imbibe water in xylem walls
  

• d. Facilitate transpiration pull

  
  

15. What is the defect of the capillarity theory in explaining sap ascent?

• a. It explains sap ascent only in leaves
  

• b. It doesn't account for water movement in phloem
  

• c. Capillarity is insufficient for high ascent in plants
  

• d. It only works in monocots

  
  

16. Which type of plant lacks root pressure?

• a. Angiosperms
  

• b. Gymnosperms
  

• c. Ferns
  

• d. Mosses