In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The SI unit of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of 1 metre against a force of 1 newton.
Science (from Latin scientia, meaning "knowledge") is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.
Science has an important part to play in our everyday existence, and there is far too much neglect of science; but its intention is to supplement not to supplant the familiar outlook.
Arthur Eddington, Science and the Unseen World (1929).
The growth of blue-green algae in our lakes, large ponds, water reservoirs and public waters constitutes a problem for our environment and for our health. These types of algae often result in a deterioration of the water quality and emit a distinctly unpleasant odour. The algae consume a lot of oxygen in the water, leaving little for other animals like fish. They also produce toxins which can cause skin irritations and are suspected to be involved in the occurrence of liver cancer.
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