Describe how water moves from the soil into the root through the stem then into the leaf to the Atmosphere.(17mks) (b) State three mechanisms by which manufactured food is translocated in plants.(3mks

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(a) - The root hairs grows between the soil particles surrounded by a film of water/soil solution; The sap   in the root hair has higher osmotic pressure than the soil solution; Water is drawn into the root hair
   by osmosis; This dilutes the cell sap in epidermal cell; relative to the sap in the adjacent cortical
   cells; Because of this, water moves into the adjacent cortical cells; until it reaches the xylem
   vessels; Within the leaf cells; some water is used in the manufacture of food; and some vapourises   when the temperatures are high; gets into the intercellular air spaces; and diffuse out of the leaf;
   through the stomatal opening; into the atmosphere; in a process called transpiration;
(Total 17 mks)

     (b) Mechanisms of translocation of manufactures food.
- Active transport;
- Mass flow;
- Surface spreading;
- Cytoplasmic streaming;(Any three correct points = 3 mks

Comments

  1. UnknownJune 14, 2020 at 11:01 PM

    This publication helps..though I don't know the meaning of cytoplasmic streaming and mass flow

    ReplyDelete

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