In science, an observation that has been repeatedly confirmed and for all practical purposes is accepted as “true.” Truth in science, however, is never final and what is accepted as a fact today may be modified or even discarded tomorrow.
The term for all of the animal species inhabiting a country, area, or region.
An alternative metabolic pathway that breaks sugars and carbohydrates into acids, gases, or alchohol to produce ATP, which is a molecule used as an energy source in all living cells. Fermentation takes place in the absence of oxygen, and is not as efficient in ATP production as aerobic respiration.
|First Law of Thermodynamics||
One of the most basic concepts in science, the First Law of Thermodynamics states that the total amount of energy in a system remains constant. Energy may be transferred from one object to another, and energy may convert from one form (say potential energy) to another (say kinetic energy)
A nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into fragments, usually two fragments of comparable mass, releasing from 100 million to several hundred million electron volts of energy; the subdivision of a cell or multi-cellular body into one or more parts and the regeneration of each part into a complete individual.
Uranium capable of undergoing fission. Fission is the splitting of one atom into two different atoms, which releases a large amount of energy.
An overflow of water onto lands that are used or usable by man and not normally covered by water. Floods have two essential characteristics: the inundation of land is temporary; and the land is adjacent to and inundated by overflow from a river, stream, lake, or ocean.
A term for all of the plant species found in a country, area, or region.
A group of interrelated food chains in a particular ecological community. A food chain is a sequence of organisms in an ecosystem in which each species is the food of the next member of the chain.
Any herbaceous plant grasses and grass-like forms; non-woody vegetation with succulent leaves and stems.
Fuels that are formed in the Earth from plant or animal remains; e.g., coal, petroleum, and natural gas.
Freshwater ecosystems are a subset of Earth's aquatic ecosystems. They include lakes and ponds, rivers, streams, springs, and wetlands. They can be contrasted with marine ecosystems, which have a larger salt content. Freshwater habitats can be classified by different factors, including temperature, light penetration, and vegetation.