A&P Ch 2 Flashcards
the chemistry of life
element
simplest form of matter to have unique chemical properties ex. Na+, H, O, K
major elements
CHNOPS 98%
CHNOPS
carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur
lesser and trace elements
Fe, Si, As, Mg2+, Cu2+
minerals
make up 4% of the body. Ca & P are most abundant, present in bones in the body. minerals originate primarily in soil and plants. function as coenzymes
atom
smallest unit that retains the properties of an element. composed of 3 subatomic particles
neutrons
neutral charge, heavy
protons
positive charge, heavy = # of electrons
atomic number
name of element
atomic mass
protons + neutrons
atomic weight
average of atomic mass of all forms of an element
molecular weight
sum of all atomic weights
electrons
negative charge, very light, form a cloud around the nucleus
distribution of electrons
in a specific energy shell/level. 1st shell hold 2, remaining shells hold 8.
bohr models
represent electron distribution
valence electrons
the electrons in the outer most shell, the number of valence electrons dictates the reactivity of an element, atoms are most stable when the valence shell is full, 2 in the first and 8 in the second. will react with other atoms to fill their outermost shell
isotopes
different forms of one elemnt that vary in the number of neutrons present
radioisotopes
unstable isotopes, nucleus decays spontaneously, giving off particles and high energy
ionizing radiation
energy that ejects electrons from atoms. creates ions that are carcinogenic. damages molecules. ex. UVrays, Xrays
ions
charged particles with unequal numbers of protons and electrons. can be a single atom or a group of atoms
cation
positive charge
anion
negative charge
electrolytes
ionize in h2o (acids, bases, salts), form solutions capable of conducting electricity. they conducts electrical currents from organs to skins surface. if they are imbalanced that can cause muscle cramps, brittle bones, coma, cardiac arrest
free radicals
chemical particles with an odd number of electrons. they come by some normal metabolic reactions of the body, radiation, chemicals. they can cause cancer, myocardial infarction (death of heart tissue)
atioxidant
a chemical that neutralizes free radicals. some examples are selenium, vitamin e, vitamin c, cartenoids
molecule
2 or more atoms joined by a covalent bond
compound
molecules composed of 2 or more different elements
molecular weight
sum of the atomic weights of all atoms
chemical bonds within molecules
ionic bonds, covalent bonds, nonpolar covalent, polar covalent
ionic bond
attraction of a cation to an anion. not very strong. ex. Na+Cl-
covalent bond
2 atoms share electrons. very strong, solid, straight line. ex. C-C, O=O, C-H
nonpolar covalent bond
equal sharing of electrons. ex. O=O, C-C, C-H
polar covalent bond
unequal sharing of electrons. ex. H-O-H
chemical bonds between molecules
hydrogen bond, van der waals forces
hydrogen bond
form between a hydrogen bonded to an electronegative atom and an electronegative atom of another molecule. ex. … = hydrogen bond
van der waals forces
interactions between electrons of one molecule and nucleus of another. holds DNA nucleotides together, holds lizards to ceilings
mixture
physically mixed, but not chemically combined
water
H & O within a water molecule are bond together with polar, covalent bonds. H is bound to O from another molecule by hydrogen bonds
properties of water
solvency, adhesion, cohesion, chemical reactivity, thermal stability
solvency
many compounds dissolve in water. essential for transport of molecules throughout the body
hydrophillic
compounds dissolve in water
hydrophobic
compounds are not soluble in water
adhesion
attraction of water molecules to other molecules. sticks to something else. lubricates organ surfaces
cohesion
water bound to water molecules. water forms even coating over surfaces. creates surface tension. sticks to itself
chemical reactivity
water ionizes readily to H+ and OH- which participate in many biochemical reactions
thermal stability
water has a very high heat capacity. much energy is needed to heat water
solution
solute+solvent. clear with small particles. ex. beer, juice
colloid
large particles, but stay mixed in the solvent. ex. milk
suspension
largest particles, which settle out with time. ex. pulpy orange juice
emulsion
suspension of one liquid in another. ex.oil & vinegar.
weight/volume
ex. IV saline is 8.5g NaCl/L. common units = mg/dL. (1dL=100mL)
percentages
ex. 5g dextrose in 100mL = 5% w/v
molarity
1 molar solution is 1 mole of a molecule/L. 1 mole = 6.023 x 10p23 molecules
electrolyte concentrations
one equivalent (Eq) neutralizes 1 mole of H+ or OH-
acids
proton donor. ex. H2CO3(carbonic acid). NH4(ammonium). HCl-(hydrochloric acid)
base
proton acceptor. ex. HCO3-(bicarbonate), NH3(ammonia). Cl-(chloride)
pH
measure of the H+ in a solution. normal pH for a human is 7.4
buffer
resist changes in pH
potential energy
stored energy
kinetic energy
energy in motion
decomposition
catabolic. AB->A+B. large molecule broken into two or more smaller ones.
synthesis reaction
anabolic. A+B->AB. two or more molecules joined to make on big one.
exchange reaction
rearrangement of atoms
reversible reactions
go in either direction depending on the relative abundance of reactants. most biochemical reactions are reversible.
reaction rates
depend on temp, pH, salinity, presence of enzymes(catalyst)
backbone of organic compounds
C & H
functional groups
hydroxyl, carboxyl, amino, phosphate
hydroxyl
OH-. carbohydrate
carboxyl
-C=O. carbohydrates, amino acids, protein
amino
-N+H3. amino acids, protein
phosphate
-PO43-. nucleotides (nucleic acids), ATP.
monomer
2monomers->polymer+H2O via dehydration synthesis
polymer
polymer+H2O->2 monomers via. hydrolysis
hydrolysis
gain water
dehydration synthesis
loose water
carbohydrates
monosaccharides, disaccharides. polysaccharides
monosaccharide
glucose, fructose. ex. fruit, processed foods, blood sugar
disaccharide
maltose, sucrose. ex. table sugar, lactose.
polysaccharide
cellulose, chitin. glycogen, . source of energy, stored in liver.
proteoglycans
large carbs with pieces of protein attached
lipids
don’t dissolve in water. hydrophobic
fatty acids
long chains of 12-24 CH. can be saturated or unsaturated. causes heart disease
saturated
lots of hydrogen bonds
unsaturated
hydrogen can be added
monounsaturated
best heart health. cant make in body
cis
same side
trans
across
triglycerides
major fat in diet, strored as triglycerides. glycerol + 3 fatty acids. long term energy, insulation, hormones
phospholipids
like a triglyceride, with one fatty acid replaced by a hydrophilic phosphate group. has both hydrophilic and hydrophobic parts
amphipathic
hydrophobic and hydrophilic parts
eicosanoids
modified fatty acid. hormone like cell signaling, vasodilation, vasoconstriction.
steroid
hydrophobic. cholesterol is parent molecule. has 4 rings of C. sex hormones, bile acids. soap that dissolves fat
protein
mononmer is amino acid. amino acids join peptide bonds. all have same basic structure with different r groups.
primary
linear sequence of amino acids. covalent bonds, peptide bonds.
secondary
hydrogen bonding along the protein backbone. double helix.
tertiary
interaction of the r groups. coiled
quarternary
interaction of 2 polypeptide chains. tetramere. correct shape is essential for function
enzyme
catalyze most chemical reactions in the body
cofactor
inorganic element necessary to enzyme function
coenzyme
organic compound required by some enzymes
vitamin c
required for collagen symthesis
folic acid
required to make hemoglobin and for development of the spinal cord
niacin
make NADH which acts in cellular respiration
riboflavin
make FMN and FAD which acts in cellular respiration
ATP
most important energy molecule.
