MCQs: 1. The movement of a plant part in response to the force of attraction exerted by the earth is called: (a) Hydrotropism (b) Geotropism (c) Chemotropism (d) Phototropism Answer. (b) Geotropism 2. A big tree falls in a forest, but its roots are still in contact with the soil. The branches of this fallen tree grow straight up (vertically). This happens in response to: (a) Water and light (b) Water and minerals (c) Gravity and water (d) Light and gravity Answer. (d) Light and gravity 3. The main function of the plant hormone called abscisic acid is to: (a) Increase the length of cells (b) Promote cell division (c) Inhibit growth (d) Promote growth of stem and roots Answer. (c) Inhibit growth 4. The growth of tendrils in pea plants is due to the: (a) Effect of sunlight on the tendril cells facing the sun (b) Effect of gravity on the part of tendril hanging down towards the earth (c) Rapid cell division and elongation...