SCIENCE REPORTER, SEPTEMBER 2014 56 DHANANJOY SINGH & NISHU MITTAL TEST YOUR KNOWLEDGE 1. In the process of diffusion movement of molecules is from: a) Lower to higher concentraon b) Higher to lower concentraon c) Either lower to higher or higher to lower concentraon d) None of these 2. Proteins called porins form pores in the membrane to allow molecule to pass through it, so do we call the channel that passes water through it? a) Pumps b) Water channel body c) Aquaporins d) Aquapore 3. What is the meaning of acve transport? a) Movement is always acve b) For acvaon it uses energy c) It uses energy to pump molecule against a concentraon gradient d) It uses sunlight for acvaon of transportaon process 4. The symbol Psi is used for what? a) Water potenal b) Solute potenal c) Thermal potenal d) None of these 5. In plant cell vacuoles are present, the membrane of the vacuole is called: a) Plasma membrane b) Cell membrane c) Tonoplast d) Leucoplast 6. What is osmoc pressure? a) Pressure applied to the process of osmosis b) Pressure acquired to prevent osmosis c) Applied external pressure to cause osmosis d) When both sides are equal in concentraon and pressure applies on both sides 7. What happens if a plant cell is placed in water (hypotonic) soluon? a) Cell remains same b) Cell shrinks c) Cell swells d) Cell dies 8. What happens if a plant cell is placed in sugar soluon (hypertonic)? a) Cell shrinks b) Cell dies c) Cell increases its acvity d) Cell decreases its acvity 9. Which is an example of imbibions? a) Movement of water across plant roof b) Water movement through xylem from roots to leaves c) Germinaon of seeds in water soaked condion d) Absorpon of water by seeds and dry wood 10. The higher plants have highly specialised vascular ssues called: a) Xylem and phloem b) Wood parenchyma c) Cambium d) None of these 11. What is the main funcon of Xylem? a) Transport of air to various plant cells b) Producon of food in plant c) Translocaon of water and mineral salts d) Translocaon of inorganic compound from leaves to other parts of the plants 12. What is the main funcon of Phloem? a) Translocaon of water and mineral salts b) Translocaon of organic compounds from the leaves to other parts of the plants c) Transport of water from one part to the other part d) No funcon is known 13. In plants the neighbouring cells are connected through: a) Cortex b) Plasmodesmata c) Cytoplasm d) Plasma membrane 14. How much water is used for photosynthesis and plant growth among total water reaching the leaves? a) 100% b) 50% c) Less than 1% d) More than 1% 15. Transpira! on is mainly through the: a) Stomata b) Leaves c) Bark d) All of the above 16. What is the immediate cause of opening or closing of stomata? a) Water flow through it b) Change in turgor pressure within the guard cells c) Change in porosity of guard cells d) All of the above 17. Which one is true? a) The direcon of movement in the phloem can be upward or downward i.e. bidireconal b) In Xylem the direcon of movement is always unidireconal i.e. upward c) Sugars, hormones and amino acids are transported or translocated through phloem d) All of the above ANSWERS: 1. b 2.c 3.c 4.a 5.c 6. b 7.c 8.a 9.d 10.a 11.c 12.b 13.b 14.c 15.a 16.b 17.d Contributed by Dhananjoy Singh & Nishu Mittal, Department of Biotechnology, IIT Roorkee. Address: Sarojini Bhawan, Room No S-67, Indian Institute of Technology, Roorkee-247667, Uttrakhand