MidTerm review Flashcards
<p>covalent bond</p>
<p>two atoms share electrons (valence electrons)</p>
<p>polar covalent bond</p>
<p>unequal sharing of electrons, causing partial ionic charge</p>
<p>non-polar covalent bond</p>
<p>equal/balanced sharing of electrons </p>
<p>ionic bond</p>
<p>electrostatic attraction between 2 oppositely charged ions - result of transfer of electrons from one atom to the other </p>
<p>anion</p>
<p>+electrons</p>
<p>cation</p>
<p>-electrons</p>
<p>4 major molecules in human body</p>
<p>carbohydrates, lipids, proteins, nucleaic acids
| </p>
<p>catabolism</p>
<p>glucose --> glycolysis or citric acid cycle</p>
<p>polar molecule</p>
<p>resulting from polar bonds, asymmetric electron sharing</p>
<p>types of cell energy</p>
<p>ATP, GTP, NADH, FADH2, pyruvate, acetyl coa</p>
<p>catabolism</p>
<p>energetically favorable reactions</p>
<p>anabolism</p>
<p>energetically unfavorable reaction</p>
<p>3 activities powered by ATP hydrolysis</p>
<p>pumping/transport
movement/mechanical
biosynthetic</p>
<p>catalysis</p>
<p>speeding a reaction by lowering the activation barrier</p>
<p>the hydrophobic portions of amino acids is typically found in/on the \_\_\_\_\_\_\_\_\_ of the conformation</p>
<p>inside</p>
<p>non-polar molecules are hydro\_\_\_\_\_\_\_</p>
<p>phobic</p>
<p>polar molecules are hydro\_\_\_\_\_\_\_</p>
<p>philic</p>
<p>Some enzymes require non-protein \_\_\_\_\_\_\_\_\_ for activity</p>
<p>cofactors</p>
<p>examples of co-factors</p>
<p>vitamins etc. </p>
<p>can the delta G from two reactions be added together</p>
<p>yes! if they're coupled</p>
<p>does delta G predict rate?</p>
<p>NO</p>
<p>what does delta G predict?</p>
<p>possibility/spontanaeity</p>
<p>a reactant makes a \_\_\_\_\_\_</p>
<p>product</p>
<p>a product is made from a \_\_\_\_\_\_</p>
<p>reactant</p>
<p>How do cells overcome the activation barrier for reactions?</p>
<p>a catalyst!!</p>
<p>A \_\_\_\_\_\_ helps cells overcome activation barriers</p>
<p>catalyst</p>
<p>is ATP stored?</p>
<p>no! it's continuously generated</p>
<p>what's an enzyme?</p>
<p>a highly specific catalyst</p>
<p>how do enzymes work?</p>
<p>they lower the activation energy of their substrate , catalyzing a reaction</p>
<p>3 ways an enzyme catalyzes (lowers activation barrier) of a substrate</p>
<p>1. binds 2 substrates and orients
2. binds and reorients electrons of 1 substrate
3. binds and strains / conforms 1 substrate to favorable transition state</p>
<p>How do enzymes maintain specificity?</p>
<p>they have unique structures and binding sites for subsrates</p>
<p>are enzymes and substrates bound by covalent bonds?</p>
<p>NO!
| </p>
<p>types of bonds that determine protein and enzyme structure:</p>
<p>electrostatic attractions
van der Waals attractions
hydrogen bond
</p>
<p>Enzymes can be \_\_\_\_\_\_\_ by molecules that resemble the substrate</p>
<p>inhibited</p>
<p>a molecule that resembles a substrate, and fills active/binding pocket without catalyzing a reaction is a \_\_\_\_\_\_\_\_\_\_</p>
<p>competitive inhibitor</p>
<p>providing \_\_\_\_\_\_ can be helpful for patients with methanol poisoning</p>
<p>ethanol</p>
<p>malonate \_\_\_\_\_\_\_ succinate hydrogenase by filling its active site and preventing the conversion of succinate to fumarate</p>
<p>inhibits</p>
<p>two types of catalytic enzyme inhibition</p>
<p>allosteric (regulatory site binding) and competitive (active site binding)</p>
<p>where does glycolysis take place?</p>
<p>cytoplasm</p>
<p>where does the CAC take place</p>
<p>the mitochondrial matrix</p>
<p>motif/scheme of signaling pathways</p>
<p>1. signal reception - on receptor, in or out
2. relay mechanism - pathway/cascade
3. downstream effects - on effector, what happens?</p>
roles of actin
muscle fibers
microvilli
projections (gut)
roles of microtubules
mechanical support cytoplasm organization transport motility - digestion chromosomal segregation
intermediate filaments
lamins
structural
subunits of actin
G-actin monomer
F-actin fibers
Arp2/3 - nucleating/branch
formin - nucleating/head
subunits of microtubules
aB heterodimers G turc centrosome GTP tubulin GDP tubulin cap of GTP tubulin
_______ is hard, _________ is easy
nucleation, elongation
intermediate filaments subunits
monomer
coiled-coil dimer
staggered tetramer
two tetramers
intermediate filament polarity (micro/macro)
polar/ non-polar
microtubule polarity (micro/macro)
polar/polar
actin polarity (micro/macro)
polar/polar
nucleating element of microtubules
G turc
nucleating element of actin
formin and Arp2/3
myosin walks on _______ in the ______ direction
actin , positive
formin adds subunits to the _____ end, and then filament extends to the ______ direction, and grows to the ______ direction
positive, negative, negative?
what causes dynamic instability?
the GTP tubulin dimers hydrolyze into GDP, and lose stability
what are the benefits of dynamic instability?
“search and capture” mode, where they explore until they find their destination
microtubule motor proteins and direction
dynine - negative
kinesin - positive
dynine purpose
motor protein, carries vesicles etc., cilia, flagella
kinesin purpose
motor protein, axonal transport etc.
what role does actin play in mitosis?
the contractile ring
what role do microtubules play in mitosis?
chromosomal organization
myosin power stroke steps
- myosin bound to actin
- ATP binds to myosin, myosin releases
- ATP hydrolyzed, myosin returns to resting position
- cross bridge forms, and myosin head binds to new position on actin
- P released, myosin heads change conformation, causing power stroke, filaments slide past eachother
- ADP release, and myosin remains bound to actin.
another name for H+
proton
if you remove an electron from hydrogen, you get…
a proton
H+ is purely____
acidic
pH stands for ______
power of hydrogen
pH of 7 is _____
neutral
hexokinase
enzyme that catalyzes breakdown of glucose to glucose 6 phosphate
substrates can bind through what bonds
ionic, hydrogen and covalent
a catalyst will ______ a reaction
speed up
does catalysis change delta G
no
two factors that determine the rate of a reaction
activation energy and concentration
an irreversible reaction has a _____ delta G going backwards
positive
if a reaction is reversible, it’s likely that delta G is _________
very small
reversible reactions generally proceed in the direction of _________
lower concentration
Glycolysis input
glucose, 2 ATP, 2 NAD+
Glycolysis output
2 pyruvate, 4 ATP, 2 NADH
Glycolysis location
cytoplasm
Fermentation input
2 pyruvate, 2 NADH
Fermentation output
2 lactate, 2 NAD+
Fermentation location
cytoplasm
CAC input
acetyl CoA / oxaloacetate, FAD, GDP, 3 NAD+
CAC output
3 NADH, 1 FADH2, 1 GTP, 2 Co2
CAC location
matrix
ETC input
NADH, FADH2 (electrons)
ETC output
ATP, NAD+, FAD
ETC location
inner mito. membrane
Glucose carbon number
6
Fructose 1,6 biphosphate carbon number
6
G3P carbon number
3
1,3 BPG carbon number
3
pyruvate carbon number
3
acetyl CoA carbon number
2
oxaloacetate carbon number
4
citrate carbon number
6
ketogenesis
starvation response, triggered by glucagon
does ketogenesis make the blood acidic?
YES! it releases ketones, which are acidic
3-phosphoglycerate number of carbons
3
citrate carbon number
6
to get G3P molecules we______
isomerize
citrate is made from _____ + ______`
acetyl CoA + oxaloacetate
poly uria
excessive urination
polydipsia
excessive thirst
polyphagia
increased appetite
are intermediate filaments polar
subunits yes, but not the macro
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