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Transport in Flowering Plants1990 Paper 2 Question 33.(a)List FOURenvironmental factors that affect the transpiration rate in vascular plants. For each factor, briefly explain how it influences the rate.(6 marks)(b)How do xerophytes reduce the rate of water loss by transpiration ?(4 marks)(c)Explain how transpiration influences the rate of water movement through a vascular plant.(4 marks)(d)Describe ONEexperiment which suggests that the phloem is the main pathway for translocation of dissolved organic substances in vascular plants.(6 marks)Ans1992 Paper 2 Question 22.(a)For each of the following, explain how its structure is related to its function(s):(i)a sieve tube(ii)a guard cell(iii)a xylem vessel(iv)a root hair cell(8 marks)(b)Describe the possible pathways for the passage of water from the surface of the root hair to the xylem and outline the mechanisms involved. Explain the critical role of the Casparian strip in this process.(12 marks)Ans1995 Paper Question 6
6.Identify the cells R, S, T and U in the following photomicrograph. From this photomicrograph, make a drawing of cell R and annotate two of its features to show their significance in transport. Suggest a mechanism of transport in each of R and U.(6 marks)Ans1996 Paper 2 Question 2 2.(a)Explain how the structural features of a dicot leaf make it an efficient organ for
photosynthesis.(8 marks)(b)Illustrate the Calvin cycle (carbon fixation) using a flow diagram and state which intermediate is used for the synthesis of carbohydrates. Name oneproduct of this synthesis.(6 marks)(c)Describe how the photosynthetic products are translocated along the phloem from a leaf to a storage organ according to the mass flow hypothesis.(6 marks)Ans1997 Paper 2 Question 66.Describe the mechanisms that bring about the movement of water in the transport systems of flowering plants and mammals. State two essential differences regarding the nature of control which affects water movement in flowering plants and mammals.(20 marks)Ans