SA TIM Flashcards
CHECK ON LEARNING
the movement of water across a semipermeable membrane
osmosis
solutions have the same osmolarity (osmotic pressure)
isotonic
solutions have more stuff dissolved in them than the neighboring compartments and tend to suck water away from the neighboring compartment
hypertonic
solutions have less stuff dissolved in them than the neighboring compartments and tend to have water sucked away
hypotonic
T/F, weak acids do not fully dissociate? what is this based on?
T
ambient pH
desire to dissociate
what is the Henderson hasselback equation?
pH=pK+log[A-]/[HA]
a molecule that produces both an acid and base is said to be this?
amphoteric
what is the equilibrium constant?
Keq=[C][D]/[A][B]
what is the dissociation constant for water?
1x10^-14
if there are more protons than hydroxyl ions it is said this solution is said to be?
acidic
if there are fewer protons than hydroxyl ions, the solution is said to be ?
alkaline
T/F, weak acids do not fully dissociate?
true
what is the extent of the weak acids ability to dissociate?
its based on ambient pH
desire to dissociate
weak acids make good or bad buffers?
good buffers
the willingness of a weak acid to absorb or release a proton is a function of its _____?
affinity
why is it important for weak acids to keep the pH stable?
because any alterations can change the protein charge and thus function
the pH where the amino acid has no net charge is called?
isoelectric point
what is the primary buffer in plasma and interstitial fluid?
bicarbonate
hypoventilation causes CO2 to accumulate in the body which causes?
respiratory acidosis
hyperventilation gets rid of too much CO2 which causes?
respiratory alkalosis
fatty acids released by the adipocytes are taken up by the?
liver
the liver converts the fatty acids into a water soluble form called?
ketones
what is the effect of ketones in the blood? what does this result? what is the effect of this?
they are weak acids and so they are dissociated acidifying the blood
metabolic acidosis or ketoacidosis
it alters secondary and tertiary protein structure producing fatigue, cerebral edema, hypokalemia and so the body responds by vomiting, acidifying the urine, and hyperventilating
what is the first law of thermodynamics?
energy cannot be created or destroyed
what happens when energy is given off?
how is this summarized into an equation that defines the first law?
radiates in the surroundings as heat (H)
used to do work (PΔV)
ΔH=ΔE+PΔV
ΔH=change in heat of system
ΔE=change in energy of the system
PΔV=amt of work done on the system
all energy from a reaction will be given off as _____?
heat
term we used for randomness?
entropy
what does the second law of thermodynamics state?
what is this in equation form?
but this does change when we want to figure out the energy available to do work
that the energy available to form heat can also be used to do organizational work
ΔE=ΔH=ΔG+TΔS
ΔE=ΔH from 1st law
ΔH=change in enthalpy of the system
ΔG=gibbs free energy, available to do useful work
TΔS=temperature x change in enthalpy, like a tax paid to the universe
ΔG=ΔH-TΔS
ΔG=more - means more energy to do work
ΔH=more - means more energy available form rxn
TΔS=more + means TΔS is more + and this makes ΔG more -
note that ΔS is not a good predictor of spontaneity, if it is negative that there is less of the total energy ΔG available to do useful work ΔG
what does -ΔG mean?
work is done
spontaneous
exergonic
what does +ΔG mean?
reaction is not spontaneous
what does -ΔH mean? does this predict spontaneity?
exothermic so heat is emitted by the rxn like a heat pack
no
what does +ΔH mean? does this predict spontaneity?
endothermic so the rxn absorbs heat like a cold pack
no
what does +ΔS mean?
the system becomes more random, good for universe
what happens when you have a -ΔG?
the reaction goes from A to B
what happens when you have a +ΔG?
the reaction goes from B to A
what is equilibrium for ΔG? How does this affect ΔG=ΔH-TΔS? Is there usable energy?
ΔG=0
TΔS=ΔH
no
what happens when intermediary metabolism in the body reaches equilibrium?
we die
what is dynamic equilibrium?
AKA steady state
there is continual flow through the path where new A’s arrive and D’s are constantly discarded
what is reason to couple reactions besides the fact that if our bodies reached equilibrium we would die?
reactions are coupled to force unfavorable reactions (+ΔG)
G-6-P to F-1,6-bisP
how do we determine ΔG?
ΔG = ΔGo + RT ln Q
what converts D-Glucose to G-6-P
Hexokinase
what converts fructose-6-P to fructose-1,6-bisP?
Phosphofructokinase
what enzyme converts fructose-1,6-bisP to glyceraldehyde and dihydroxyacetone-P?
aldolase, but triode phosphate isomerase converts between glyceraldehyde and dihydroxyacetone-P
what converts glyceraldehyde-3-P to 1,3-bisphosphoglycerate?
glyceraldehyde-3-P dehydrogenase
what converts 1,3-bisphosphoglycerate to 3-phosphoglycerate?
phosphoglycerate kinase
what converts phosphoenolpruvate (PEP) to pyruvate?
pyruvate kinase
at the end of glycolysis what is the net yield of ATP and NADH for a total of how much ATP?
4 total ATP and 2 NADH, however there is an expense of 2 ATP so all in all, 8 ATP after converting NADH
in mammals what converts the pyruvate to acetyl-CoEnzyme A
pyruvate dehydrogenase
what is pyruvate converted to when O2 is low or absent?
lactate, so the ETC is shut down…but the reaction is reversible
what keeps glycolysis running?
NAD+
in aerobic conditions what is pyruvate converted too?
acetyl CoA which then fuels the TCA cycle
what is acetyl CoA comprised of?
acetate and Coenzyme A
with respect to the conversion of pyruvate to AcCoA, what is formed, what inhibits PDH? where is PDH located?
NADH
Acetyl CoA and NADH
mitochondrial matrix
how many ATPs are produced from the TCA cycle?
24 ATPs , 2 direct and 22 indirect
T/F, the TCA cycle continues in the absence of oxygen?
F
what is the energy balance after glucose is fully catabolized?
aerobically, 38 ATP
anaerobically, 2 ATP
what is the primary key regulatory protein of the TCA cycle? what are the other two?
citrate synthase
isocitrate dehydrogenase
alpha keto glutarate
what enzymes of the TCA cycle are for energy harvest? of them which are direct and indirect
isocitrate dehydrogenase, indirect alpha keto gluturate, indirect succinyl CoA synthase, direct succinate dehydrogenase, indirect malate dehydrogenase, indirect
what enzyme of the TCA cycle is membrane bound?
succinate dehydrogenase
what enzyme does malonate inhibit?
succinate DHase (competitive)
what enzyme does arsenite inhibit?
PDH and alpha ketoglutarate DHase (non-comp)
what enzyme does fluoroacetate inhibit?
aconitase (competitive)
what intermediate of the TCA cycle is the major exit point?
alpha-ketoglutarate controlled by the regulatory enzyme on either side
this process produces AcCoA but the TCA cycle will stop if there is no more of this enzyme to accept it?
glycolysis
oxaloacetate
what is the enzyme used to replenish OAA if necessary?
anapldrotic reactions
what enzyme uses the energy from one phosphate on ATP to glue a CO2 onto pyruvate to yield OAA?
pyruvate carboxylase
what is current directly proportional too?
voltage
what is voltage a measure of? what is this considered as?
the energy drop that the electrons have from flowing from A to B
electromotive force
this is the net tendency to gain or lose electrons?
redox potential
the more positive the redox potential has what type of effect on electrons?
the greater the tendency to accept electrons, good oxidizing agent
the more negative the redox potential has what type of tendency on electrons?
the greater the urge to donate electrons, good reducing agent
T/F, electrons will always move to the molecule with the most positive redox potential?
T
positive redox potential means what for the spontaneity of the reaction?
it is spontaneous
so for the overall electron transport overall the energy produced from the ΔG prime can be used to make how many ATP?
6 ATP/NADH because it takes about 8kcal/mol to make a phosphate bond and -52.6 kcal/mol is produced from the energy of the electron transport chain and half the amount of the ATP is lost as heat with 3 ATPs resulting
which complexes of the ETC are used for electron transport?how about for oxidative phosphorylation?
complex 1-4
complex 5
what enzyme is associated with complex I?
NADH Q reductase
NADH Dehydrogenase
what are the electrons passed onto after they leave complex I?
ubiquinone
what is complex II also known as?
succinate dehydrogenase
complex III is also known as what?
cytochrome reductase
what is unique about cytochrome C in terms of the electrons it can hold?
4 electrons
what is complex IV also known as?
cytochrome oxidase
what parts of the ETC pump hydrogens across the inner mitochondrial membrane?
complex I, ubiquinone between complex I/II and complex III, complex IV; also moving 2 hydrogens acrost so total of 6 hydrogens
what regulates electron transport and oxidative phosphorylation?
ADP availability
oxygen availability
how does ADP enter the matrix and ATP leave?
translocase
this poison affects complex I but not II?
amytal rotenone
this poison affects movement of electrons from CYTB to CYTC?
antimycin A
this poison affects complex IV, the cytochrome A and A3?
cyanide
carbon monoxide
azide
these uncouplers collapse the the H+ gradient?
thermogenin
2,4 DNP
how does NADH get from the cytosol into the matrix?
malate aspartate shuttle
G-6-P can continue on with glycolysis or go through what other two pathways?
glycogen synthesis or pentose phosphate pathway (NADPH synthesis and Ribose-5-P for nucleotide synthesis)
where is glycogen most concentrated?
liver
where is glycogen most plentiful?
muscle
what type of polysaccharide is glycogen? how are the glucose molecules attached?
branched chain homopolysaccharide, only alpha D glucose is found here
via alpha 1,4(90%-forming straight chains) and alpha 1,6(10%-forming branches) glycosidic bonds
what enzyme adds UDP-glucose to the growing chain? what is the primer so that the glycogen granule can be produced? what enzyme does this? what linkage is formed?
glycogen synthase
glycogenin
glycogen initiator synthase
alpha-1,4; the UDP-glucose is added to the carbon 4
what enzyme converts glucose-1-p to UDP glucose? what else is produced?
UDP-glucose pyrophosphorylase
pyrophosphate and this broken down by pyrophosphatase
in the formation of UTP from UDP, what enzyme regenerates the UTP used to make UDP glucose?
nucleoside diphosphokinase
if glycogen synthase only present, what polysaccharide would this be?
amylose
what is the benefit of having glycogen branched?
more soluble
more free #4 carbons
what enzyme is responsible for creating the alpha-1,6 branch?
glucosyl-alpha-4,6-transferase (branching enzyme) from a portion of a chain part of a alpha-1,4 linkage from glycogenin
what enzyme breaks down glycogen alpha-1,4 glycosidic bonds? alpha-1,6 glycosidic bonds
glycogen phosphorylase
debranching enzyme, 2 domains
domain 1: glucosyl-4,4-transferase
domain 2: alpha-1,6-glucosidase
what enzyme interconverts G-6-P to G-1-P?
phosphoglucomutase
the net rate of synthesis and breakdown is controlled by regulating what two enzymes?
glycogen synthase and glycogen phosphorylase
what two factors signal the mobilization of glucose?
glucagon and epinephrine
amino acid metabolism is an important component of?
nitrogen metabolism
what are the two important components to nitrogen metabolism?
amino acid pool
protein turnover
where do the pools of amino acids in the body come from?
dietary protein digestion
degradation of proteins in the body
de novo synthesis
why have protein turnover at all?
It allows a cell to be adaptable to new situations/environments, so increase adaptability leading to increased survival
what enzyme regulates protein turnover?
ubiquitin
how many grams of protein does the body need per day?
56 g/day
low protein dietary intake can produce shortages in essential AAs for protein systhesis leading to increased protein breakdown leading to this disease?
kwashiorkor disease
what are the two major secretions of the stomach?
HCL and pepsinogen(converted to pepsin by HCL or more pepsin)
most protein digestion occurs where in the digestive system?
small intestine
what are the pancreatic enzymes?
small intestine enzymes?
trypsin
chymotrypsin
elastase
carboxypeptidase
aminopeptidase
why is trypsin important?
in the pancreas it is trypsinogen then it is activated to trypsin via enteropeptidase which then activates the other enzymes from the pancreas moving into small intestine like:”
elastase
carboxypeptidase
chymotripsinogen
how are the glucose stores arranged in the body?
how much does the body use? the brain? and glucose stores last the brain for how many days?
190 g in the form of glycogen
20 g in the form of body fluids
for a total of 210 g
160 g of glucose/day
the brain uses 120g (75%)
1.5 days of brain function
what are the alternative sources of glucose?
lactate
amino acids
glycerol
all converted to pyruvate(main source for pyruvate during bad times is alanine) than to glucose via gluconeogenesis
where does gluconeogenesis primary take place?
liver and the kidney to a lesser extent
