BIO XI 4.1

CHAPTER 11. TRANSPORT IN PLANTS

 

KEY TERMS:

 Translocation, diffusion, facilitated diffusion, porins, symport, antiport, uniport, active transport, passive transport, water potential, osmosis, osmotic potential, plasmolysis, isotonic, hypotonic, hypertonic, turgor pressure, imbibition ,Apoplast &symplast pathway, root pressure, guttation, capillarity, transpiration, adhesive & cohesive forces

BIO XI 4.1.1

Q.1. Define free energy.

Q. 2 . What is water potential? What is the unit of measuring water potential? Name the

factors that influence water potential.

Q. 3 . Differentiate the apoplastic movement of water from symplasic movement.

Q. 4 . What happens to the water potential of a solution (i) when pressure applied is more

(ii) when more solutes are added?

Q. 5. Why apoplastic movement of water is not possible beyond the cortex?

Q. 6. What is diffusion? What is its significance?

BIO XI 4.1.2

Q. 7 . What is the covering membrane of vacuole?

Q. 8. What are plasmodesmata?

Q. 9. What is osmosis? Describe an experiment to demonstrate osmosis.

Q. 10. What is plasmolysis?

Q. 11.  Define the imbibition. What are the two conditions  needed for osmosis to take

place?

BIO XI 4.1.3

Q. 12. Discuss briefly the two important theories that explain the upward movement of 

water.

Q. 13. How is water transported up to the leaves in trees which may be more than 100 m

high?

Q. 14. What is transpiration? Mention its significance.

Q. 15. How does the following factor influence the rate of transpiration?

(i)light (ii)temperature (iii) humidity (iv)wind (v)water.

Q. 16. Describe the cohesion theory of movement of water through the xylem in tall trees.

BIO XI 4.1.4

Q. 17. Explain how does the opening & closure of stomata occur.

Q. 18. What is the significance of transpiration?

Q. 19. Explain why xylem transport is unidirectional and phloem transport is bi-

directional?

Q. 20. Explain pressure flow hypothesis of translocation of sugars in plants.

Q. 21. How is mycorrhizal association helpful in absorption of water & minerals?