(a) (i) Name the process by which root hair cells absorb water
Answer: Osmosis
(1 mark)
(ii)Define the process in (a)(i).
Answer: (The net) movement of water molecules from a region of low solute concentration to a region of high solute concentration through a semi permeable membrane//movement of water from hypotonic region to hypertonic region.
(1 mark)
(b) Based on Diagram 1, which of the region of X and Y has
(i) lower water concentration
Answer: Y
(ii)high water concentration
Answer: X
(2 marks)
(c) Draw an arrow on Diagram 1 to show the movement of water in a root hair cells of plant R.Answer:
(1 mark)
(d) A farmer applied a large quantity of fertilizers on plant R. Predict and explain what will happen with plant R in a few days.
Answer: F1 - Plant R will wilt
P1 - Excess of fertilizer causes the environment surrounding to be hypertonic to the cell sap
P2 - (a net) movement of water molecules from inside to outside of the cell by osmosis.
(3 marks)
(e) Photograph 1 shows two fresh raw eggs with their shells removed with acid which have been soaked for one hour into solution P and Q respectively.
Explain the process occur in both P and Q.
Answer:
P: F1 - fresh raw egg in P is floating
P1 - solution P is hypertonic to the cytoplasm of fresh raw egg.
P2 - (a net) movement of water molecules from the inside to outside of the cell by osmosis
Q: F2 - fresh raw egg in Q is sink.
P3 - solution P is hypotonic to the cytoplasm of fresh raw egg.
P4 - (a net) movement of water molecules from the outside to inside of the cell by osmosis.
