Biochem Exam 1

dielectric constant

the measure of the ability of a substance to store electrical energy (polarizability)

higher

the ____________ the dielectric constant, the weaker the interaction is between charges

lower

dehydration would lead to a __________ dielectric constant

hydrogen bonding

Interaction between a covalently-bonded hydrogen atom on a donor group (-OH or -NH) and a pair of bonded electrons on an acceptor group (O=C or N=-)

60

water is __% of our body weight

dipole-dipole

water has a high heat capacity and heat of vaporization due to _____________ interactions

heat of vaporization

water's high _______________ prevents dehydration and decreases body temperature

dielectric constant

water's high _____________ is due to the ion-dipole interactions it experiences & it causes ions to exist in biological solutions

amphipathic

_____________ molecules are those which have both hydrophilic and hydrophobic properties, such as fatty acids, lipids, and detergents

40

intracellular fluid (ICF) makes up __% of body weight and includes K+ proteins and organic ions

20

Extracellular fluid (ECF) makes up __% of body weight and includes NaCl and NaHCO3 in solution

osmotic pressure

hydrostatic pressure produced by a solution in space divided by a semipermeable membrane due to a differential in the concentrations of solute

osmole

non-SI unit of measurement that defines the number of moles of a chemical compound that contribute to a solution's osmotic pressure

osmolality

measure of osmoles of solute per kilogram of solvent

salt

water flows toward high concentrations of salt

Na+, K+

the ecf should have high _________ and low ________________

K+, Na+

the icf should have high _________ and low ________________

excessive water intake

hyposmotic expansion

loss of salt (kidneys)

hyposmotic contraction

edema

isosmotic expansion

hemmorage

isosmotic contraction

drinking saline

hyperosmotic expansion

severe sweating

hyperosmotic contraction

hyposmotic

lower salt concentration than currently in ECF and ICF

hyperosmotic

higher salt concentration than currently in the ECF and ICF

isosmotic

approximately equal to the current ECF and ICF concentrations

non-covalent interactions

electrostatic interactions, dipole interactions, hydrogen bonding, dispersion forces, hydrophobic interactions

lowers

dehydration causes fewer water molecules to take up the same relative volume, which results in lengthened and weakened hydrogen bonds, __________ the dielectric constant, and increases the attraction between charges and less ion availability --> muscle contraction is affected

permanent dipole

a molecule that is made up of atoms with largely different electronegativity values and therefore results in an electron distribution that results in a permanent partial positive and partial negative portions of the molecule

induced dipole

a molecule whose atoms generally do not result in a partial charge but do allow for a change in electron distribution when a neighboring charge is nearby, thus inducing a dipole in the molecule

hemoglobin

The affinity that ________________ has on oxygen is decreased when the pH of the solution is decreased.

lower

When the solution is at a _______ pH, hemoglobin tends to release more oxygen because it doesn't have as much affinity to keep the oxygen bound to the heme group.

7.4

physiological pH

lungs, kidneys

organs that regulate blood pH

Arrhenius acid

molecule that releases protons in water

Arrhenius base

molecule that releases hydroxide ions in water

Bronsted-Lowry acid

molecule that donates an H+ to another molecule

Bronsted-Lowry base

molecule that accepts H+ from another molecule

Lewis acid

molecule that accepts a pair of electrons from other molecules

Lewis base

molecule that donates a pair of electrons to other molecules

large

acids with ________________ Kas are strong

small

acids with __________________ pKas are strong

1

when selecting a buffer for a solution, use a weak acid/base that has a pKa/b within ____ pH unit(s) of the target pH

pKa

pH = ___ + log([A-]/[HA])

acidosis

abnormally high acidity of the blood and other body tissues (low pH)

respiratory acidosis

caused by diseases of the respiratory system; patients cannot eliminate CO2 from the blood effectively

metabolic acidosis

caused by the release of acidic substances into the bloodstream (i.e. exercising & lactic acid, diabetes & ketoacids)

alkalosis

abnormally high alkalinity of the blood and other body tissues (high pH)

respiratory alkalosis

caused by hyperventilation

metabolic alkalosis

caused by vomiting, ingesting baking soda/tums, kidney failure

saturated

fatty acid with no double bonds in the tail

unsaturated

fatty acid with double bonds in the tail

(head:tail), (c or t), delta, (carbons with double bonds)

naming fatty acids

triacylglycerols

glycerol backbone with three fatty acyl groups; used for energy storage in animals

liquid

unsaturated fatty acids tend to be ________________ at room temperature

solid

saturated fatty acids tend to be ___________ at room temperature

phospholipid

glycerol-3-phosphate backbone with two fatty acyl groups attached by an ester linkage to glycerol carbons 1 and 2

sphingolipid

consist of an 18-carbon amino-alcohol backbone rather than glycerol

glycerophospholipids

significant fraction of the membrane derived of glycerol-3-phosphate and composed of 2 acyl side chains R1 and R2 derived from fatty acids and 1 hydrophilic R3 group

cholesterol

steroid lipid found in membranes that changes the permeability of the membrane

decreases

at high temperatures, cholesterol ______________ membrane fluidity

increases

at low temperatures, cholesterol ______________ membrane fluidity

saponification

the process in which triglycerides are combined with a strong base to form fatty acid metal salts during the soap-making process

myelin

a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers; made up of 75% lipid and 25% protein

inner mitochondrial membrane

made up of about 25% lipid and 75% protein

compartmentalization, structure, regulation, communication

functions of the membrane

PI

greater than 10% of membrane lipid in bran, primary source of signaling metabolites (arachidonic acid, DAG, phosphatidylinositol phosphates (PIP2 and IP3))

PE

higher levels in CNS, smaller head group allows tiger packing, capable of hydrogen bonding

PC

higher levels in plasma membrane, present in lipoproteins (LDL and HDL), produces DAG and acetylcholine

PS

found in inner leaflet except during apoptosis, movement to outer leaflet is accomplished by functional scramblase and non-functional flippase, provides charged surface for prothrombinase complexes to bind

CL

only found in mitochondrial membranes, 20% of mitochondrial lipids, sensitive to oxidative damage, contains 4 fatty acyl chains

flippase

enzyme that flips membrane PL inward; requires ATP

floppase

enzyme that flops PL out (particularly PS)

scramblase

enzyme that causes random redistribution of membrane PL

Asp, Glu, Lys, Arg, His

amino acids with charged polar side chains

pKa

when the pH of a solution is close to the ____ of a form of an amino acid, that form is the predominant form

lipid raft

an area in the membrane where there is a high concentration of cholesterol, and a different composition of carbohydrates, proteins and other lipids compared to the rest of the membrane