| A | B |
|---|
| molecule | The smallest unit of an element or compound, consisting of one or more like atoms in an element and two or more different atoms in a compound. |
| mixture | Two or more substances that are not chemically united and that exist in no fixed proportion to each other. |
| proton | A positively charged part of an atom found in the nucleus |
| neutron | A neutral part of an atom, found in the nucleus of all atoms, except hydrogen. |
| electron | A negatively charged part oa an atom, found circling around the nucleus. |
| nucleus | A positively charged area within an atom, composed of neutrons and protons, and possessing almost all of the mass of the atom, but occupying only a small fractgion of the volume of the atom. |
| ion | An electrically charged atom formed by the loss or gain of one or more electrons |
| compound | A particle composed of two or more elements. |
| matter | Anything that has mass and takes up space. |
| isotope | One of two or more atoms having the same atomic number but different mass numbers. |
| technology | The application of science to make products or tools that people |
| scientific method | Ways or steps to follow to solve problems. |
| control | A sample that is treated like the other experimental groups |
| constant | The variables that stay the same. |
| dependent variable | The factor being measured. |
| independent variable | The variable that is changed. |
| hypothesis | A prediction that can be tested. |
| model | This represents things that happen too slowly, too quickly, or are too big or too small to observe directly. |
| experimental research design | This is used to answer scientific questions by testing a hypothesis through the use of a series of carefully controlled steps. |
| descriptive research | Answers scientific questions through observation. |
| cell wall | the definite boundary or wall that is part of the outer structure of the cell |
| endoplasmic reticulum | a network of tubular membranes that is involved in the transport of materials within the cell |
| vacuole | A small cavity in the cytoplasm of a cell, which contains water, food or waste. |
| mitochondrion | an organelle in the cytoplasm of cells that functions in energy production |
| nucleus | a central part of the cell with a double membrane that directs the growth, metabolism and reproduction of the cell |
| ribosome | a tiny part of the cell that produces protein |
| cell membrane | a thin layer that encloses the cell and controls what goes in and out of the cell |
| cytoplasm | the cell substance between the cell membrane and the nucleus, it is full of proteins that control cell metabolism |
| lysosomes | a part of the cell that breaks down food molecules |
| golgi bodies | a part of the cell that’s function is to prepare and store chemical products in the cell, and to secrete these outside the cell |
| atmosphere | The gaseous envelope surrounding the earth. |
| troposphere | The first layer above the surface and contains half of the Earth's The first layer above the surface and contains half of the Earth's The first layer above the surface and contains half of the Earth's atmosphere. Weather occurs in this layer. |
| stratosphere | The region of the upper atmosphere characterized by little change in temperature as you go up. |
| mesosphere | The portion of the atmosphere above the earth's surface, characterized by temperatures that decrease as you go up. |
| thermosphere | The region of the upper atmosphere in which temperature increase as you go up. |
| ionosphere | Part of the thermosphere but very important. This area makes long distance radio communication possible by reflecting radio waves back to Earth. |
| exosphere | Where the atmosphere merges into space. This is the upper limit of our atmosphere and extremely thin. |
| ozone layer | A region of the upper atmosphere containing a high concentration of ozone that absorbs solar radiation. |
| meteorology | the science dealing with the atmosphere and its phenomena, including weather and climate. |
| aurora borealis | a display of colored lights in the sky, also called northern lights, caused by the interaction of particles from the sun with the upper atmosphere. |
| core | The central portion of the earth, believed to be composed mainly of iron & nickel in a molten state. |
| mantle | The portion of the earth, between the crust and core. |
| crust | The outer layer of the earth, about 22 miles deep under the continents and 6 miles deep under the oceans. |
| sedimentary rock | Rock that has been formed through the deposition & solidification of sediment. These are often deposited in layers, and frequently contain fossils. |
| igneous rock | Rock formed by the solidification of molten magma. |
| metamorphic rock | Rock that was once one form of rock but has changed to another under the influence of heat and/or pressure. |
| weathering | Various mechanical and chemical processes that cause exposed rock to decompose. |
| stalactite | A deposit, usually of calcium carbonate, shaped like an icicle, hanging from the roof of a cave. |
| stalagmite | A deposit, usually of calcium carbonate, resembling an inverted stalactite, formed on the floor of a cave. |
| geology | The science that deals with the dynamics and physical history of the earth. |
