| A | B |
|---|
| magnetic pole | Either of two limited regions in a magnet at which the field of the magnet is most intense, each of which is designated by the approximate geographic direction to which it is attracted |
| main sequence | continuous and distinctive band of stars that appear on plots of stellar color versus brightness |
| mass | look up |
| mass number | the integer nearest in value to the atomic weight of an atom and equal to the number of nucleons in the nucleus of the atom |
| matter | the substance or substances of which any physical object consists or is composed |
| Mean | average of a set of numbers |
| mechanical energy | energy of motion commonly associated with moving machines and devices |
| mechanical weathering | The breakdown of rock into smaller fragments by physical processes such as frost wedging |
| Meiosis | Process of gamete formula |
| membrane | Anatomy. a thin, pliable sheet or layer of animal or vegetable tissue, serving to line an organ, connect parts, etc. |
| metabolism | the sum of the physical and chemical processes in an organism by which its material substance is produced, maintained, and destroyed, and by which energy is made available |
| Metalmeteorite | look up |
| Metric | any type of measurement used to gauge some quantifiable component |
| miscible | That can be mixed in all proportions. Used of liquids |
| mitochondria | an organelle in the cytoplasm of cells that functions in energy production. |
| Mitosis | method of cell division |
| Mixture | Any combination or blend of different elements, kinds, qualities |
| Model | a representation containing the essential structure of some object of event in the real world |
| molecule | look up |
| momentum | look up |
| motion | an act, process, or instance of charging place |
| mutation | look up |
| Natural Selection | The process by which forms of life having traits that better enable them to adapt to specific environmental pressures, |
| nebula | an immense cloud of gas (mainly hydrogen) and dust in interstellar space |
| neutron | an elementary particle having no charge |
| niche | the status of an organism within its environment and community (affecting its survival as a species) |
| nitrogenous bases | (building blocks of DNA and RNA): adenine, guanine, thymine, cytosine, and uracil. |
| Noble gas | And element in Group 8A of the periodic table, the S and P sublelvels of the highest occupied energy level are filled |
| Non-Metal | An element that tends to be a poor conductor of heat and electric current |
| non-renewable resource | any natural resource ( petroleum or minerals) that cannot be replenished naturally with the passage of time |
| nuclear fusion | process by which multiple atomic nuclei join together to form a single heavier nucleus |
| nuclear reactions | a reverse movement or tendency; an action in a reverse direction or manner |
| nucleus | a central part about which other parts are grouped or gathered |
| nucleus | central part of the cell containing the genetic information of the cell |
| nucleus | a fundamental arrangement of atoms, as the benzene ring, that may occur in many compounds by substitution of atoms without a change in structure |
