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Biochemistry - ANSexplain physiological processes and detect, diagnose and treat disease
Chemistry - ANSconsiders composition of substances and how they change
Matter - ANSanything that takes up space and has mass (weight) - composed of elements
Elements - ANScomposed of chemically identical atoms
92 - ANSnaturally occurring elements
26 - ANSartificially created elements
Types of elements (3) - ANS-bulk elements
-trace elements
-ultratrace elements
Bulk elements - ANSrequired by the body in large amounts
Trace elements - ANSrequired by the body in small amounts
Ultratrace elements - ANSrequired by the body in very minute amounts
Atoms - ANSsmallest particle of an element
Atoms-composed of subatomic particles (3) - ANS-proton
-neutron
-electron
Proton - ANScarries a single positive charge
Neutron - ANScarries no electrical charge
Electron - ANScarries a single negative charge
Nucleus - ANS-central part of atom
-composed of protons and neutrons
Electron shells - ANSelectrons move around the nucleus of subatomic particles
, Atomic number - ANS-number of protons in the nucleus of one atom
-equals the number of electrons in the atom
Atomic weight - ANS-the number of protons plus the number of neutrons in one atom
-electrons do not contribute to the weight of the atom
Isotopes - ANS-atom with the same atomic numbers but with different atomic weights
(atoms with the same number of protons and electrons ** but a different number of neutrons**)
Oxygen often forms - ANSisotopes (O16, O17,O18)
Unstable isotopes are - ANSradioactive, they emit energy or atomic fragments
Radioactive isotopes - ANSrelease energy or pieces of themselves to become stable (atomic
radiation)
Types of radioactive isotopes - ANS- alpha radiation
- beta radiation
- gamma radiation
Molecule - ANSparticle formed when two or more atoms chemically combine
Compound - ANSchemical combinations of elements
Molecular formulas - ANSdepict the elements present and the number of each atom present in
the molecule
ex: H2 H2O
Bonds - ANSatoms combine with other atoms
-ionic bonds
-covalent bonds
First electron shell - ANShold up to 2 electrons
Second electron shell - ANShold up to 8 electrons
Third electron shell - ANShold up to 8 electrons
Full shell = - ANSstable atom
Octet Rule - ANSwhen atoms react in a way that leave the outer most shell full