A doffer is someone who removes bobbins, pirns or spindles holding spun fiber such as cotton or wool from a spinning frame and replaces them with empty ones. Historically, spinners, doffers, and sweepers each had separate tasks that were required in the manufacture of spun textiles. From the early days of the industrial revolution, this work, which requires speed and dexterity rather than strength, was often done by children. After World War I, the practice of employing children declined, ending
For a plant organ to bend in response to a stimulus, differential growth of cells on either side of the organ is required. For example, for the stem of a plant to bend toward a light source, cells on the shaded side of the stem near the shoot tip must elongate faster than cells on the lighted side.
Photo in phototropism means light. Light is a stimulus that plants have response to. A stimulus could be weather, touch, gravity or light. The orientation of a plant or other organism in response to light, either toward the source of light or or away from it. It is usually observed in plants, but can also take place in other organisms such as fungi. The cells on the plant that are farthest from the light have a chemical called auxin that reacts when phototropism occurs which causes the plant cells to get longer on the furthest side of the light.