A&P ch 2

anything that has mass and occupies space

• solid - definite shape and volume
• liquid - definite volume, changeable shape
• gas - changeable shape and volume
• plasma

the capacity to do work or put matter into motion

• kinetic
• potential

• chemical - stored in bonds of chemical substances
• electrical - movement of charged particles
• mechanical - directly involved in moving matter
• radiant or electromagnetic - wavelike properties (eg. visible light, x-rays)

• can't be broken down by ordinary chemical means
• unique physical and chemical properties

building blocks for elements

• oxygen
• carbon
• hydrogen
• nitrogen

• no charge
• mass = 1 amu

• positive charge
• mass = 1 amu

• negative charge
• negligible mass (0 amu)

• atomic symbol - 1 or 2 letter chemical shorthand for each element
• atomic number - number of protons in the nucleus
• atomic mass - mass of protons + mass of neutrons
• atomic weight - avg of mass numbers of all isotopes of the element

structural variations of elements that differ in the number of neutrons they contain

2 or more atoms bonded together

• 2 or more different kinds of atoms bonded together
• can be separated only by breaking bonds unlike mixtures
• all are homogeneous

• 2 or more components physically intermixed, no chemical bonding between components, can be separated physically
• solution
• colloid
• suspension

• homogeneous mixture
• solvent and solute

• emulsion
• heterogeneous mixture
• particles don't settle out
• undergo sol-gel transformations
• think mayo or jello

• heterogeneous mixture
• solutes tend to settle out
• think vinaigrette or blood

• electrons occupy up to seven electron shells around nucleus
• first shell is full with 2 electrons, all other shells are full at 8 (octet rule)
• outermost shell is valence shell

• stable and unreactive
• outermost shell is full

• formed by transfer of electrons
• attraction of opposite charges results in ionic bonding
• ionic compounds form crystals instead of individual molecules

negative charge because it has gained electron(s)

• positive charge
• has lost electron(s)

sharing of electrons

• equal sharing of electrons
• CO₂

• unequal sharing of electrons
• water

• attractive force between electropositive hydrogen of one molecule and an electronegative atom of another molecule
• common between dipoles like water
• also act as intramolecular bonds, holding large molecules in 3D shape

• synthesis - bonds are formed
• decomposition - bonds are broken
• exchange - bonds are made and broken

• do not contain carbon
• water, salts, many acids and bases

• contain carbon
• usually large
• covalently bonded
• carbs, fats, proteins, nucleic acids

• high heat capacity - prevents sudden temp changes
• high heat of vaporization - useful cooling mechanism
• polar solvent properties - dissolves and dissociates ionic substances, body's major transport medium
• reactivity - necessary part of hydrolysis and dehydration synthesis reactions
• cushioning - protects some organs from trauma eg. cerebrospinal fluid

• ionic compound that dissociates in water
• contains cations other than H⁺ and anions other than OH^-
• ions conduct electrical currents in solution
• ions play specialized roles in body functions

• electrolyte
• proton donor (release H⁺ in solution)

• electrolyte
• proton acceptors (take up H⁺ from solution)
• bicarbonate ion (HCO₃^-) and ammonia (NH₃) are important bases in the body

• pH = the negative logarithm of H⁺ in moles per liter
• neutral - pH 7, eg water
• acidic - more H⁺, lower pH,
• alkaline - less H⁺ (or more OH^-), higher pH

• interferes with cell function
• can dmg living tissue
• slight change in pH can be fatal
• regulated by kidneys, lungs and buffers

• mixture of compounds that resist pH changes
• convert strong (completely dissociated) acids or bases into weak (slightly dissociated) ones

water molecule leaves creating bond between 2 monomers

water molecule is added to polymer providing the necessary components for it to split into its monomers

• sugars and starches
• contain C, H, and O

• monosaccharide
• disaccharide
• polysaccharide

• major source of cellular fuel (glucose)
• structural molecules (ribose sugar in RNA)

simple sugars containing 3-7 C atoms (CH₂O)_n

• double sugars
• too lg to pass through cell membranes

• polymers of simple sugard (starch, glycogen)
• not very soluble

• contain C, H, O and sometimes P
• insoluble in water

• triglycerides (neutral fats)
• phospholipids
• steroids
• eicosanoids

• neutral
• composed of 3 fatty acids bonded to a glycerol molecule
• functions - energy storage, insulation, protection
• fatty acids - saturated and unsaturated

• glycerol + 2 fatty acids and a phosphorus containing group
• head and tail regions have different properties
• cell membrane structure

• interlocking 4-ring structure
• cholesterol, vitamin D, steroid hormones, bile salts

• derived from fatty acid in cell membranes
• prostaglandins

• polymers of amino acids
• contain C, H, O, N and sometimes S and P

covalent bond formed when carboxyl group of one molecule reacts with amino group of another molecule, releasing water molecule

• primary
• secondary (alpha helix or beta sheet)
• tertiary
• quaternary

• strandlike, water insoluble, stable
• keratin, elastin, collagen

• compact, spherical, water-soluble, sensitive to environmental change
• specific functional regions (active sites)
• antibodies, hormones, molecular chaperones, enzymes

• ensure quick and accurate folding and association of proteins
• assist translocation of proteins and ions across membranes
• promote breakdown of dmg or denatured proteins
• help trigger immune response
• produced in response to stressful stimuli eg O₂ deprivation

biological catalysts - lower activation energy speeding up reactions

• substrates bind to active site
• energy is absorbed, bond is formed, water is released
• product is released
• product is dipeptide (peptide bond)

• DNA & RNA
• contain C, O, H, N and P
• built of nucleotides - N containing base, pentose sugar and a phosphate group

• adenine, guanine, cytosine and thymine
• RNA has uracil instead of thymine

• double-stranded helical molecule in nucleus of cell
• provides instructions for protein synthesis
• replicates before cell division ensuring genetic continuity

• single-stranded molecule mostly active outside of nucleus
• 3 kinds carry out the DNA orders for protein synthesis - mRNA, tRNA, and rRNA

phosphorylation - terminal phosphates are enzymatically transferred to and energize other molecules, these molecules then perform cellular work using the phosphate bond energy