Ch 2 Flashcards
The more H+ makes body fluids more
Acidic
Generates action potentials (neural impulses)
Potassium
The smallest unit of matter that retains the properties and characteristics of an element
Atoms
Which structure separates thoracic cavity from the abdominalpelvic cavity
The diaphragm
Isotopes
Same element, different number of neutrons
(Radioactive isotopes) half life
Time required for half of the radioactive atoms in a sample to decay into a more stable form
Ion
An atom that has lost or gained an electron. Positive or negative charge. Ex: Ca2+
Molecule
Two or more atoms sharing electrons. Ex: O2
Compound
A substance that can be broken down into two or more different elements. Ex: H2O or NaCl
Have an impaired electron in its outermost shell. Sources include UV rays from sunlight, ozone, x-rays, pollution, cigarette smoke.
Free radicals
Inactivates oxygen derived free radicals. Ex: Diet foods rich in selenium, vitamin C, zinc, beta carotene: fruits and vegetables
Antioxidants
Electronegativity
Ability to attract electrons
When does a chemical bond occur?
When atoms are held together by forces of attraction
What determines the likelihood that an atom will form a chemical bond with another atom?
The number of electrons in the valance shell
Ionic bonds
Bonds between positively charged and negatively charged atoms
Ionic bonds are super strong by themselves, but are able to break into individual + and - ions by:
Electrolytes
Covalent bonds
Two or more atoms share electrons instead of transferring them
Is water polar or non-polar?
Polar
Synthesis reactions – anabolism
When two or more ions, atoms or molecules combine to form new and larger molecules
Decomposition reactions- catabolism
When large molecules are split into smaller atoms, ions, atoms or molecules
Exchange reactions
Includes both synthesis and decomposition reaction. Just exchanging.
Oxidation reduction reactions
These reactions transfer electrons between atoms and molecules, and always a curtain parallel. Oxidation – loss of electrons and energy release. Reduction – gain of electrons and energy gain. (OIL RIG)
Exergonic reactions
Release more energy than they absorb
Endergonic reactions
Absorb more energy than they release