The Proscience Portal

Transport L3

VIDEOS

NOTES

ASSIGNMENT

Section A: Multiple Choice Questions (1 mark each)

  1. The main tissues involved in the transport of water and minerals in plants are:
    a) Phloem
    b) Xylem
    c) Parenchyma
    d) Collenchyma
  2. Transpiration pull helps in:
    a) Photosynthesis
    b) Transport of food
    c) Upward movement of water
    d) Respiration in leaves
  3. Which tissue is responsible for translocation of food in plants?
    a) Xylem
    b) Cambium
    c) Phloem
    d) Meristem
  4. The process of loss of water in the form of vapour from aerial parts of the plant is called:
    a) Translocation
    b) Transpiration
    c) Transportation
    d) Photosynthesis
  5. In the process of translocation, food is moved:
    a) Only upward
    b) Only downward
    c) In both directions
    d) In random directions

Section B: Assertion and Reasoning (1 mark each)

Choose the correct option:
a) Both A and R are true and R is the correct explanation of A
b) Both A and R are true but R is not the correct explanation of A
c) A is true but R is false
d) A is false but R is true

  1. Assertion (A): Phloem transports sucrose from leaves to other parts of plant.
    Reason (R): Translocation in phloem uses energy.
  2. Assertion (A): Xylem transport is bidirectional.
    Reason (R): Water is needed in leaves as well as roots.

Section C: One-Word Answer Questions (1 mark each)

  1. What are the conducting tissues in plants?
  2. What is the name of the process responsible for pulling water upward through xylem?
  3. What is the energy source used in translocation?

Section D: Short Answer Questions (2 marks each)

  1. State any two differences between xylem and phloem.
  2. Define translocation. Mention one direction and one substance transported during this process.

Section E: Long Answer Questions (3 marks each)

  1. Explain the transport of water in plants with reference to transpiration pull and root pressure.
  2. Describe the mechanism of translocation in phloem, including the role of ATP and osmotic pressure.

KEY

Section A: Multiple Choice Questions

  1. b) Xylem
  2. c) Upward movement of water
  3. c) Phloem
  4. b) Transpiration
  5. c) In both directions

Section B: Assertion and Reasoning

  1. a) Both A and R are true and R is the correct explanation
  2. d) A is false but R is true
    (Xylem transport is unidirectional — from roots to leaves)

Section C: One-Word Answer Questions

  1. Xylem and Phloem
  2. Transpiration pull
  3. ATP

Section D: Short Answer Questions

  • Xylem transports water and minerals; Phloem transports food.
  • Xylem transport is unidirectional; Phloem transport is bidirectional.

Translocation is the movement of food (mainly sucrose) from leaves to other parts of the plant.
Direction: Both upward and downward
Substance: Sucrose/Glucose

Section E: Long Answer Questions

Water is absorbed by root hairs and moves through xylem.

  • Root pressure pushes water up a little.
  • Transpiration pull due to evaporation of water from stomata creates a suction force that pulls water upward through xylem vessels.
    This movement is unidirectional from roots to leaves.

Translocation in phloem involves:

  • Sugar is loaded into phloem using ATP (energy).
  • This increases osmotic pressure and water enters from xylem, creating a pressure flow.
  • The food moves to the sink (e.g., roots, fruits), where sugar is unloaded, and water returns to xylem.
    Thus, phloem transport is energy-dependent and bidirectional.