Semester Test Review 2 nd Semester
1. Element A substance that cannot be separated or broken down into simpler substances by chemical means.
2. Chemical compound A chemical substance consisting of two or more different chemically bonded chemical elements.
3. Chemical energy Energy released by a chemical reaction or absorbed in the formation of a compound.
4. Chemical reaction The process by which one or more substances change to produce one or more different substances.
5. Newton s First Law of Motion An object at rest remains at rest, and an object in motion remains in motion at constant speed and in a straight line unless acted on by an unbalanced force.
6. Newton s Second Law of Motion The acceleration of an object depends on the mass of the object and the amount of force applied.
7. Newton s Third Law of Motion Whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first.
8. Constant velocity A speed that does not change how fast it is, or the direction that it is in.
9. Force A push or pull exerted on an object in order to change the motion of the object; it has size and direction.
10. Inertia The tendency of an object to resist being moved or, if the object is moving, to resist a change in speed or direction until an outside force acts on the object.
11. Law of Conservation of Matter Law that states that matter cannot be created or destroyed in an isolated system.
12. Net force The combination of all of the forces acting on an object.
13. ph A value that is used to express the acidity or basicity (alkalinity) of a system.
14. Acceleration The rate at which velocity changes over time; an object accelerates if its speed, direction, or both change.
15. Conservation of Energy Energy cannot be created or destroyed but can be changed from one form to another.
16. Electric Current The rate at which charges pass through a given point; measured in amperes.
17. Electrical Energy Energy made available by the flow of electric charge through a conductor.
18. Electromagnet A coil that has a soft iron core and that acts as a magnet when an electric current is in the coil.
19. Electromagnetic spectrum All of the frequencies or wavelengths of electromagnetic radiation.
20. Energy Transformation The change of energy from one form to another.
21. Magnetic field Exists in the region around a magnet in which magnetic forces can act.
22. Balanced force When the net force on an object is 0 N.
23. Unbalanced force When the net force on an object is not 0 N.
24. Density The ratio of the mass of a substance to the volume of the substance.
25. Amplitude The maximum distance that the particles of a wave s medium vibrate from their rest position
26. Wave A periodic disturbance in a solid, liquid, or gas as energy is transmitted through a medium
27. Wavelength The distance from any point on a wave to an identical point on the next wave.
28. Refraction The bending of a wave as the wave passes between two substances in which the speed of the wave differs.
29. Reflection The bouncing back of a ray of light, sound, or heat when the ray hits a surface that it does not go through.
30. Frequency The number of waves produced in a given amount of time.
31. Heat energy All of the kinetic energy due to random motion of the particles that make up an object. Ex. Hot water
32. Light energy Energy produced by the vibrations of electrically charged particles. Ex. Lamp
33. Electricity The energy of moving electrons. Ex. outlet
34. Mechanical energy The amount of work an object can do because of its kinetic and potential energy. Ex. Riding a bike
35. Sound energy Energy caused by an object s vibrations that are carried through the air. Ex. guitar
36. Motion An object s change in position relative to a reference point.
37. Organelles One of the small bodies in a cell s cytoplasm that is specialized to perform a specific function (little organs).
38. Cell wall A rigid structure that surrounds the cell membrane and provides support to the cell. It is found only in plant cells.
39. Cytoplasm A gel-like substance in which all the parts of the cell rest. This helps give the cell its form and hold all the cell s organelles in place.
40. Nucleus A membrane-bound organelle that contains the cell s DNA and has a role in processes such as growth, metabolism, and reproduction. This organelle is found in eukaryotic cells only. It is the control center of the cell. Eukaryotic Cell Prokaryotic Cell
41. Homeostasis The maintenance of a constant internal state in a changing environment. http://www.bookofodds.com/var/site/storage/imag es/media/images/a0063-body- temperature/27405374-1-eng-us/a0063-body- Temperature_leader.jpg
42. Unicellular Consisting of one cell
43. Multicellular Consisting of more than one cell http://blog.mary.com/wp-content/uploads/2012/05/random_picture6.jpg http://images.tutorvista.com/content/feed/u2077/ Multicellular%20Organisms.jpg
44. Atoms The smallest unit of an element that maintains the properties of that element. http://d1jqu7g1y74ds1.cloudfront.net/wpcontent/uploads/2010/02/c-atom_e1.gif http://www.myschoolhouse.com/courses/c/ 6/Images/10.atom.gif
45. Molecule The smallest unit of a substance that keeps all of the physical and chemical properties of that substance. http://www.ozoneminnesota.com/wp-content/uploads/2012/12/ozone-molecule.jpg
46. Tissue A group of similar cells that perform a common function.
47. Organ A group of tissues that carry out a specialized function of the body.
48. Organ System A group of organs that work together to perform body functions.
49. Qualitative Data Data that involves descriptions and characteristics. Example: Color and appearance The cat looks scared. The cat has green eyes. The cat has long whiskers. The cat has a dry nose. The cat has stripes.
50. Quantitative Data Data that deals with numbers and can be measured. Example: Length, height, weight, and time. The mouse weighs 0.5 kg. The mouse has two ears. The frog is 20cm long. The frog has one tongue. The mouse took a ride on the frog for 56 seconds.