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Answer then ask a question.
Question 1:
What type of solvent would be best for favoring Sn1?
Question 1:
What type of solvent would be best for favoring Sn1?
Originally posted by UCLAstudent
Passive immunity: receiving antibodies produced in a rabbit
Active immunity: receiving a booster shot
Of conduction, convection, and radiation, which involves the transfer of translational kinetic energy?
Originally posted by Cerberus
Convection?
The note A has a frequency of 233Hz, what is the frequency of the next octave?
Originally posted by UCLAstudent
Correct!
466 Hz
What would be the effect of demyelination of an axon?
Originally posted by UCLAstudent
Calcium
What is the neurotransmitter released at the neuromuscular juntion?
orgo yummmy...Originally posted by jhk43
Rank the acidities of the alpha hydrogen
ketone
amine
acid chloride
aldehyde
beta keto ester
ester [/B]
Originally posted by LUBDUBB
orgo yummmy...
beta keto ester
aldehyde
ketone
ester
(acid chlorides)
amines (no carbonyl)
as for acid chlorides...they are very reactive, that is they will lose the leaving group (Cl) very readily and leave behind an electrophile subject to nucleophillic attack. I would probably stick it right under esters.
That being said, I think you got me on this one JHK.
Next question:
Inhibiting the electron transport chain would also inhibit which of the following: glycolysis, Krebs cycle or fermentation?
Originally posted by LUBDUBB
Next question:
Inhibiting the electron transport chain would also inhibit which of the following: glycolysis, Krebs cycle or fermentation?
Originally posted by jhk43
The cell would continue glycolysis. some pyruvates would still go into the mitochondria for krebs, but some would start the fermentation process to compensate for the lack of NAD+.
Eventually Krebs would stop (due to lack of NAD+) and all pyruvate would try to enter fermentation. Note that at a certain point, some aerobes cant live in high lactic acid or ethanol conditions and die.
Btw, cyanide is a drug that stops the ETC.
Originally posted by babinski bob
Here's the CORRECT answer for the fxnl group acidity question
B-ketoester > acid chloride > aldehyde > ketone > ester > amide > amine
The stronger the e- withdrawing character of the carbonyl, the more acidic the alpha-hydrogen. Acid chlorides are more acidic than aldehydes, ketones, esters, amides, amines because of the electron withdrawing character. A general trend for the acidity of alpha H's is that they parallel C=O reactivity. So acid chlorides are more reactive than aldehydes which are more reactive than ketones which are more reactive than esters which are more reactive than amides.
Originally posted by LUBDUBB
Ok...let's consider this...alpha hydrogens are on the carbon next to the carbonyl. The more acidic the alpha hydrogen, the more readily it will get plucked off, thus forming a carbanion. Just like when an aldehyde loses its hydrogen to give an enolate ion.
Now, an acid chloride will lose its Cl very readily, leaving behind and electrophile. My problem is that I have never seen an acid chloride lose its alpha hydrogen to become a carbanion.
Someone help me out.
Originally posted by Persistence101
In EK's Ochem book, they state that just like aldehydes, acid chlorides donate their alpha hydrogen. They make stronger acids than aldehydes due to the electron withdrawing Cl.
Ok...let's consider this...alpha hydrogens are on the carbon next to the carbonyl. The more acidic the alpha hydrogen, the more readily it will get plucked off, thus forming a carbanion. Just like when an aldehyde loses its hydrogen to give an enolate ion.
Now, an acid chloride will lose its Cl very readily, leaving behind and electrophile. My problem is that I have never seen an acid chloride lose its alpha hydrogen to become a carbanion.
Q: If a rocket take off at an initial velocity of 100 m/s, 75 degrees of the horizontal, and its engine stops working after 11 seconds, what is the maximum height the rocket achieves?
Originally posted by redgrover
I know this was way back in the thread, but we need more information to solve this problem. Note that the rocket engine stops firing after 11 seconds. Yes, we have v0, but the rocket will be accelerating due to the firing of its rocket engine for another 11 seconds. We either need either the force (which will allow us to derive the acceleration) of the engine or the acceleration of the rocket engine before we can solve.
jhk43 said:you eat a steak. stomach gets stimulated by Sympathetic or PS? Ach or NE/E?
jhk43 said:you eat a steak. stomach gets stimulated by Sympathetic or PS? Ach or NE/E?
LUBDUBB said:Ach released by the PS nervous system to stimulate smooth muscle contractions.
Why is mitochondria only inherited maternally?
LUBDUBB said:Ach released by the PS nervous system to stimulate smooth muscle contractions.
Why is mitochondria only inherited maternally?
Nuel said:If I guess right: only the nucleus of the Y chromosome fuses with the ovum.
Nuel said:Let me be the first to post a question with options . . . hmmm.. now we are doing it MCAT style.
Physics:
Fluid element can undergo non-turbulent flow because:
A. irrotational flow suggests no net angular velocity.
B. eddy currents are present to oppose turbulent flow effects.
C. there are no streamlines which cross to oppose turbulent flow.
D. fluctuating fluid density always implies incompressible fluids.
Nuel said:Let me be the first to post a question with options . . . hmmm.. now we are doing it MCAT style.
Physics:
Fluid element can undergo non-turbulent flow because:
A. irrotational flow suggests no net angular velocity.
B. eddy currents are present to oppose turbulent flow effects.
C. there are no streamlines which cross to oppose turbulent flow.
D. fluctuating fluid density always implies incompressible fluids.
Nuel said:Lubdubb, you are extremely smart! I give you a 40 next Saturday.
LUBDUBB said:Not at all, I've just been drilling this info in my head for a really long time.
Good Luck
The surge in LH before ovulation is caused by what?
Nuel said:GnRH is responsible for the surge of LH, and FSH too.
LUBDUBB said:yeah... rise of estrogen --> surge in GnRh ---> surge in LH-->ovulation.
Ok one more q & a then i gotta get back...
What is the function of the RNA primer in DNA replication?
Nuel said:GnRH is responsible for the surge of LH, and FSH too.
jhk43 said:what causes the GnRH rise? positive feedback for estrogen? whys it positive sometimes, and negative feedback other times?
Nuel said:Certain antimetabolite drugs can cause people to lose weight by uncoupling the chemiosmotic machinery thus making the mitochondrial lipid bilayer:
A. permeable to H+ because ATP synthase is deactivated in the
mitochondrial matrix by such changes and no ATP is produced.
B. permeable to H+ because the mitochondrial catalytic sites of ATP synthase
remain active but cannot produce ATP.
C. impermeable to H+ because ATP synthase is deactivated in the
mitochondrial matrix by such changes and no ATP is produced
D. impermeable to H+ because the mitochondrial catalytic sites of ATP
synthase remains active but cannot produce ATP.
jhk43 said:i believe Radius is max at the equator, min at the N pole..
F=GMm/R^2
g~M/R^2
since g~1/R^2, g is max at smaller radius, so escape velocity max @ north pole?
Cerberus said:PS..."rest and digest"
Damage to which part of the eye would cause difficulty in vision in low light situations?
Nuel said:Certain antimetabolite drugs can cause people to lose weight by uncoupling the chemiosmotic machinery thus making the mitochondrial lipid bilayer:
A. permeable to H+ because ATP synthase is deactivated in the
mitochondrial matrix by such changes and no ATP is produced.
B. permeable to H+ because the mitochondrial catalytic sites of ATP synthase
remain active but cannot produce ATP.
C. impermeable to H+ because ATP synthase is deactivated in the
mitochondrial matrix by such changes and no ATP is produced
D. impermeable to H+ because the mitochondrial catalytic sites of ATP
synthase remains active but cannot produce ATP.
jhk43 said:or rod cells