Unformatted text preview: on & electron quantity identical)
– all exhibit same chemical properties • Radioisotopes: unstable nuclei, decay giving off energy/matter. • Elements are neutral: – can be detected; use as # electrons = # protons
tracers to follow molecules • Atomic number = # of protons
in biological reactions. • Atomic mass = Also, many applications in # of protons + # of neutrons
medicine. Electrons Have Potential Energy
• Potential energy: energy due to the arrangement or position of matter
– An electron’s potential energy is proportional to its’ distance from the nucleus; determined by which energy level or shell the electrons occupy Energy absorbed by an atom can result in electrons moving to higher levels (shells), or even out of the atom altogether.
Electron transfers between molecules = transfers of energy; these processes fuel metabolism. Distribution of Electrons in an Atom
• Electrons are in constant motion around the nucleus; occupy regions called orbitals, and these occur in discrete layers around the nucleus...
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This note was uploaded on 08/16/2011 for the course BIOL 1361-1362 taught by Professor Any during the Spring '08 term at University of Houston.
- Spring '08