Agrobacterium tumefaciens is a bacterium that causes crown gall disease in plants by transferring genetic material into plant cells. Scientists use it in genetic engineering and tissue culture to introduce useful genes into crop plants successfully.
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The correct option is (iii). Meristematic cells have thin walls, dense cytoplasm and a large prominent nucleus. These features support rapid cell division, active metabolism and continuous growth, allowing plants to increase in length, girth and regeneration.
The correct option is (ii) phloem. Phloem transports food prepared in leaves to roots and other plant parts. Malfunctioning phloem disrupts movement of sugars and nutrients, affecting growth, storage and normal metabolic activities in plants.
The correct option is (iii). Epithelial tissues are thin to allow rapid exchange of gases, nutrients and wastes across them. Their thin structure supports efficient absorption, secretion and diffusion in organs like lungs, intestines and blood vessels.
In the straight-leg jump, ankles, knees and hips remained stiff and less flexible. In the normal jump, knees and ankles bent naturally while hips flexed slightly, helping absorb shock, maintain balance and produce smoother, safer movement.