Previous exam topics Flashcards
what is an acid?
proton donator
(its dissociation makes conj base)
what is a base?
proton acceptor
(its dissociation makes a conj acid)
weak acids and bases exist in:
equilibrium with conj species
what is an example of a weak acid and base?
acid: carboxylic acid
base: amine
what is the most imp physiological buffer
bicarbonate
what bonds are in 2,3,4 protein structure?
hydrogen bonds and non covalent bonds
when do buffers work best?
at pKa
what is secondary amino acid structure?
a- helix and b-sheets
what holds primary protein structure together?
covalent bonds
what is an oncones?
mutation at one amino acid
what happens in M phase
mitosis
amino acids determine?
protein folding
what occurs during G1
interphase, increases in size, and is active biochemically
(technically G1, S and G2 are interphase)
what are key features of 2nd messagner systems?
specificity
amplification
augmentation
rapid signal transduction
the goblins have what structure?
no beta structure, a helix connected by turns
what occurs with sickle cell disease?
gu becomes val
makes hydrophobic
most cells are in the ______ stage of cell cycle
G0
what happens during s phase?
cell copies DNA makes sister chromatids
What is an oncogene
Mutation that takes place at a single amino acid
Example RAS G12V mutation
What happens at the G1 phase?
Longest, cell grows and makes new proteins and organelles
what happens during G2 phase
cell prepares for mitosis by growing and syn new proteins and lipids
What Happens during the S phase?
Synthesis phase, DNA replicates making Sister cromatids
What occurs at the m phase
Mitosis
What are some things that occur during apoptosis?
•Outer Membrane blebbing
•Shrinking
•Condensation of the nucleus
•Fragmentation of chromosomes
•Formation of cytoplasmic vacuoles
•The cell fragments generated by apoptosis are taken up and
eliminated by neighboring cells and phagocytes
give a brief summary of extrinsic apoptotic signaling
mediated by cell death receptors
formation of disc
recruitment of pro-casp 8
activation of effector caspases 3,6,7
can feed into intrinsic from here
give a brief summary of intrinsic apoptotic signaling
-marked by central event: MOMP
-release of cytochrome C
-trigger of complex of caspase 9 and APAF1 via CARD and APAF1
-Casp 9 recruits effector caspases 3,6,7
what will happen with loss of function in CASP8 mutations?
suppress apoptotic signaling allowing cell survival
what is rRNA syn by?
syn by RNA polymerase I
what does rRNA do?
rRNA + protein= ribosomes
transferred to cytoplasm to become parts of large and small sub units of ribosome
what is tRNA syn by?
RNA poly III
what does tRNA do?
-carry amino acids to ribosomes, -anticodon sequence is complementary to mRNA being read
when is a tRNA said to be charged?
when the correct amino acid is attached to the 3’ end
what is mRNA?
made from DNA used as template for protein syn
what is the TCA cycle?
uses acetyl coA to make ATP and water
coenzyme A needs which vitamin?
pantothenic acid
what steps of TCA need coA?
1,4,5
what kind of pathway is TCA?
amphibolic, meaning it does catabolism and anabolism
what are the main points of entrt of electrons from fuel ox to enter ETC?
Compex 1 and 2
(e- collect at coQ)
what ratios change the ETC?
high NADH/NAD slows
high ATP/ADP slows
what are some inhibitors of TCA?
barbiturates 1, antimycin A- 3, cyanide 4, oligomycin atp synthase blocker
how is fat mobilization regulated?
adenylate cyclase helps it enter, triacylglycerol lipase hydrolyzes bonds to release FA and glycerol
what tissues do not really use FA and which ones use a lot?
nervous not a lot
muscle a lot
what helps transfer FA from adipose to other tissues?
albumin
what is needed to transport FA into mitochondria?
carnitine palmitoyl transferases (CPT1)
what prevents CPT1?
malonyl CoA
(makes sense cause if FA syn is happening you dont want them to be broken down right away)
what is the most important type of fatty acid oxidation?
B- ox
what is the important enzyme of b-ox?
acytyl co-a dehydrogenase
what inhibits acyl coA dehydrogenase?
hypogycin (from unripe fruit of ackee tree)
where do you get most ATP?
b ox of palmitate
where does ketone body formation occur?
mitocondria
what is the major site of acetoacetate formation and why?
liver because it is where HMG CoA synthase
during fasting what two things are increased?
fat mobilization and ketogenesis (ketone body formation)
how are dietary lipids digested early?
lingual lipase in mouth
gastric lipase in stomach
what are the essential FA?
lineoic
l-lineoic
archidonic
how are FA digested in small intestine?
*pancreatic lipase
co-lipase
bicarbonate
bile salt
bile sat is most useful in what form?
anionic form
what is the function of co-lipase?
attract and anchor pancreatic lipase to surface of emulsion particle
once in the small intestine what happens to the FA?
carried by bile salt, make mixed micelle, cross epithithealial boarder, and the FA and 2-MG reforms TGs, can make chylomicrons
what can occur if there is a lipid malabsorption?
steatorrhea
ldl has the most:
cholesterol and chol esters
Chylomicrons and vldl has the most:
TGs
what does A-I do
activator of LCAT, choI pick up
what does B-100 do?
LIGANT FOR LDL receptor
what does C-II do?
activates LPL
what does apoprotein E do?
Ligand for LDL and chylomicron remnant
what does LPL do?
processing chymicrons
what is difference between Lcat and Acat?
Lcat in bLood with HDL
what is difference between HSL and LPL?
H is fat mobiLization
L is fat storage
what happens to chylomicrons in blood?
HDl comes along, donates E and CII, chylo binds to lpl breaks down to FA and glycerol
(Fa to adipose, muscle, gly to liver)
what happens to vldl in blood?
hdl donates E and CII, lpl, Fa gly, HGT makes IDl to ldl
lpl is stimulated by:
CII and insulin
what does statin and cholestyramine do?
more ldl receptors
humans lack the enzyme to digest:
a- 1,3 and b 1,4
the glucose in oral dextran is from:
sucrose
starch is digested by:
a-amylase
on what from of carbs can be transmitted across epitheium?
monosaccharides
what receptors do monosaccharides go through in the lumen?
slgt1: glucose and galactose
GUlt5: fructose
what receptor monosaccharides take to blood?
all glut5
sglt receptors couple what?
Na and glu/gal
(cl and water follow)
glut5 is directly stim by
insulin
where does folate get carbons?
glycine
what does folate do with the carbon?
carries to syn purines and to B12
what is FH4
active form of folate, it accepts carbons can make purines (A and G), Pyrim (t) and gets trapped as methyl or B12 form
what happens to FH4 once it transfers methyl?
recycled except for in absence of B12 when it cant be recycled (folate trap)
what can folate deficiency cause?
inflammation` of tongue, mouth and ulcers
exampes of BCAA?
lucine
isolucine
valine
how are BCAA metabolized?
a-ketoacid dehydrogenase
what is maple surup urine?
decrease in a-ketoacid dehydrogenase causing buildup
what’s treatment for maple syrup urine?
limit BCAA
what is classical PKU?
phenylalanine cant be transformed to tyrosine, so too much phe
how to treat PKU?
avoid phe and aspartame
what is alkaptonuria?
defect in homogentisate dioxygenase
accumuation of homogentisate (back urine, eyes, ears, teeth)
what is homocystinuria?
defect in cystathionine synthase accumulates homosysyine in blood and urine
how to treat homocystinuria?
high dose Vit B6
what is a free radical?
molecule with one or more unpaired electrons
what is a NOXs?
NADPH oxidases, transfer electrons
what are mitochondrial ros?
electrons escape from ETC from complex 2 and 3, forming ROS
what is respiratory burst?
macrophages and neutrophils take in lots of O2 and release ROS to kill microorganisms
superoxide’s are converted to H2O2 by:
superoxide dismutases
SOD requires:
zinc and copper
what is the primary thing needed for preventing lipid peroxidases
vit E
go over metabolism difference in diabetes 1 and 2
