Science Glossary

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Australian scientists: For information regarding what is happening (and what has happened) in Australian science, contact the Australian Academy of Science at www.science.org.au/aashome.htm.

Classification system for living things: Scientists have found and described approximately 1.75 million species on Earth. In addition, new species are being discovered every day. Classification is one way to make sense of the diversity of life. There are many classification systems, but the one most commonly used by scientists is the Linnaean system of classification. In this binomial (two-name) system of classification, scientists name animals and plants by naming the genus and species of the organism. The first word is the genus and the second is the species. The first word is capitalised and the second is not. Humans are scientifically named Homosapiens. An abbreviation of this name as H. sapiens, where the genus is only represented by the first letter, may also appear in scientific literature.

Earth’s atmosphere: The atmosphere is the thin layer of gases that surrounds the Earth and is retained by Earth’s gravity. It contains about four-fifths nitrogen and one-fifth oxygen, with trace amounts of other gases. The atmosphere protects life on Earth by absorbing solar radiation and reducing temperature extremes between day and night. The layers of the atmosphere are the troposphere, stratosphere, mesosphere, thermosphere, ionosphere and exosphere. The atmosphere has no abrupt cut-off. It slowly becomes thinner and fades away into space. The Karman line, at 100 kilometres above the Earth’s surface, is frequently used as the boundary between Earth’s atmosphere and space.

Ecological footprint: An ecological footprint (or eco-footprint) is a measure of our ecological performance. It tracks the quantity of resources individuals (or organisations, cities, regions, nations or the global population) consume and compares this amount to the resources nature can provide. It indicates how much biologically productive land and water area a given population occupies in order to produce the resources it consumes and to absorb its waste, using prevailing technology.

Emerging sciences: Traditional science discipline boundaries are being revised as new knowledge in science creates broader and novel applications of science. The emerging sciences include:

Nanotechnology: Further information can be found at www.nano.gov

Biotechnology: Further information can be found at www.gtac.edu.au and www.biotechnology.vic.gov.au

Green chemistry: Further information can be found at www.chem.monash.edu.au/green-chem

Synchrotron science: Further information can be found at www.synchrotron.vic.gov.au.

Energy: Energy is defined as the amount of work required to change the state of a physical system. Energy may be classified as potential (stored) energy or kinetic (moving) energy. Forms of energy include thermal, mechanical, electrical, gravitational, elastic, chemical, heat, light and sound. Energy may be transformed from one form into another. The presence of energy is revealed only when a change takes place. Animals obtain their energy from food. Toasters and washing machines use electricity as their energy supply.

Energy transfer: This refers to the ways in which energy can be moved, for example heat transfer by convection, conduction and radiation.

Energy transformation: This refers to energy conversions from one form to another. Energy can be readily transformed from one form into another. Potential energy (stored energy, for example chemical, gravitational and elastic) may be converted to kinetic energy (moving energy, for example electrical, mechanical) and from kinetic energy to heat, light or sound energy. For example, using a battery to power an electrical heater converts chemical energy into electrical energy, which is then converted into thermal energy. Allowing elevated water to move down a hill transforms stored potential energy into the kinetic energy of moving water and turbines, which in turn may be transformed into electrical energy by a generator.

Geological processes: Geological processes have shaped and continue to shape the Earth. These processes can occur at the Earth’s surface; for example, physical and chemical weathering, removal by gravity such as landslides and mudflows, erosion, and the building up and breaking down effects of running water, groundwater, waves, currents, tides, tsunamis, wind and glaciers). They can be caused by events inside the Earth; for example, continental drift, folding, faulting and vulcanism. They can also be caused by events away from the Earth; for example, meteorites. The activities of living things, including humans, also impact significantly on geological processes.

Investigations: Investigations provide students with the opportunities to frame and pose questions which can be tested scientifically. Students work independently or in small groups or teams. They plan their work and select processes and equipment with attention to safety and draw conclusions from their data. They comment on the accuracy and reliability of the processes used and data collected, and complete a report of their investigation which can be presented in a range of formats.

Mass: Mass and weight are not the same. In science these words have special meanings. Mass is a measure of the amount of matter (material) in an object and is commonly measured in grams (g) or kilograms (kg).

Material Safety Data Sheets (MSDS): MSDS provide the information needed to allow the safe handling of hazardous substances used at the workplace. Schools are required to comply with these procedures for the management of hazardous substances. An MSDS should provide sufficient information to enable users of the hazardous substances to handle them safely, to understand their potential dangers and to take appropriate action in case of an emergency.

Models: Models are ways of representing complex structures and relationships. They are used to simplify a more complex arrangement; for example, the structure of matter represented through particle and atomic theory.

Scientific method: This involves the principles and empirical processes of discovery and demonstration of considered characteristics of, or necessary for, scientific investigation. Scientific method generally involves the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to prove or disprove the hypothesis, and a conclusion that validates or modifies the hypothesis. Science by inquiry or science by discovery is also integral to investigations in science.

Scientific Procedures Premises License (SPPL): An SPPL is required when animals are used to teach science. For further information contact Schools Animal Welfare Project, Bureau of Animal Welfare, Department of Primary Industries (Victoria) at www.dpi.vic.gov.au and/or the Department of Education and Training (Victoria) at www.sofweb.vic.edu.au.

Scientific vocabulary: This refers to the words used by scientists to accurately describe matter, organisms, processes and systems. These words have an exact meaning or definition, and application. Sometimes these words are used incorrectly or imprecisely when applied in everyday use.

Sustainability: Sustainability is an ecological, economic, social and political concept. A sustainable society is one that meets the needs of the present without compromising the ability of future generations to meet their own needs. In the Science domain, issues which need to be considered for sustainability include: the conservation of biodiversity and ecological integrity; dealing judiciously with risk, uncertainty and irreversibility; ensuring appropriate valuation of environmental assets; integration of environmental and economic goals in government and institutional policies and activities; social equity (both intragenerational and intergenerational); and community participation.

Resources:

Systems: Systems consist of inputs, processing and outputs for a group of organs (or cells) that work together to provide living things with advantages for survival. Systems can be found in plants and animals (including humans). Systems work alone and with other systems. The human body is an example of a complex system and illustrates the progression from cells to tissues to organs and then systems. Maintaining homeostasis, or a stable internal environment, enables humans to survive.

The Law of Conservation of Energy: This law (also known as the First Law of Thermodynamics) states that energy can be converted from one form to another, but it cannot be created or destroyed.

The Law of Conservation of Mass: This law states that matter changes form, but it cannot be created or destroyed. This means that for any chemical process in a closed system, the mass of the reactants must equal the mass of the products.

Units of measurement: A unit is a particular physical quantity, defined and adopted by convention, with which other particular quantities of the same kind are compared to express their value. The International System of Units (SI) is founded on seven base quantities, assumed to be mutually independent, as shown in the table below:

Base quantity SI base unit  
  Name Symbol
amount of substance

mole

mol

electric current

ampere

A

length

metre

m

luminous intensity

candela

cd

mass

kilogram

kg

thermodynamic temperature

kelvin

K

time

second

s

Further information about SI units can be found at the Bureau International des Poids et Mesures website at www.bipm.org.

Variables: Variables are factors that can and do affect the outcome of experiments. Some variables can be controlled during experiments. These are known as control variables. The impact of some variables can be reduced by refining procedures and/or repeating the experiment many times. Only one variable should be included in the design of an experiment.

Weight: Weight and mass are not the same. Weight is a measure of the force of gravity pulling on a mass and is measured in newtons (N). Under ordinary conditions the mass of an object can be said to be constant (the object’s mass will be the same at different locations in the Universe). The weight of an object is not constant, since the force of gravity varies from place to place (the object’s weight varies depending on its location in the universe). For example, Earth’s moon is smaller than Earth and pulls objects towards it less strongly. A given object will therefore have the same mass on Earth and on the moon, but its weight on the moon will be about 16% of the weight as measured on the Earth. A human with a mass of 50 kg on Earth, for example, will weigh 500 N on Earth. On the Moon, this person will still have a mass of 50 kg but will only weigh 80 N.