MCAT Biochemistry

Enzyme functions (4)

provide suitable environment for reaction, provide amino acid residues to act as acids/bases, lover activation energy of transition state, weaken bonds of reactants

Saturated hydrocarbon

A carbon molecule that only has single bonds to hydrogen

Urea cycle

process that occurs in the liver that removes excess nitrogen from the body through amino groups like ammonia

What does D and L glucose look like

What is a epimer

A configuration of a molecule that is different at only one chiral carbon

What is the difference between a alpha and beta glyosidic bond

Ass DOWN, Boobs UP

What is the pKa of the carbonyl group and when is is de/protonated

2 and its protonated <2 and deprotonated >2 (-)

What is the pKa of the amino group and when is it de/protonated

9 and its protonated <9 (+) and deprotonated >9

What does the Gq protein do (describe pathway)

Gq activates phospholipase C, which cleaves the membrane forming PIP2. PIP2 is cleaved into DAG and IP3. IP3 can open calcium channel in the ER with increases intracellular Ca

What is amphipathic mean?

Having both polar and nonpolar regions in one molecule

What is the charge of the DNA backbone

The backbone of DNA has a negative charge due to the phosphates

What does pyruvate dehydrogenase do

Turns pyruvate to acetyl CoA which will eventually lead to ATP production

Contrast the glucose production of the liver and muscles

Liver creates glucose to balance body wide glucose levels while muscle creates glucose to use for itself

In an isoelectric focusing experiment, explain where a negative and positive protein would move in it

In isoelectric focusing, electrons move from the anode to the cathode (electric field). A negative protein will not move with the electric and move toward the anode. A positive protein will move with the electric field toward the cathode.

Compare SDS PAGE and reductive SDS PAGE

SDS PAGE breaks non-covalent bonds while reductive SDS PAGE breaks down covalent bonds (like disulfide bridges)

Proteases are ____ and only cleave __-amino acids

Proteases are stereospecific and only cleave L-aminoacids

In a enzyme activity plot, what does a sigmoidal curve show

Cooperativity

Cofactor

non-protein, inorganic molecule/metal ion that allows enzymes to be effective

Coenzymes/vitamins

small organic molecules that allow enzymes to be effective

Number of Hydrogen bonds between adenine and thymine

2

Number of hydrogen bonds between guanine and cytosine

3

Energy change when breaking a bond

Endothermic

Energy change when forming a bond

Exothermic

What is the structure of a GCPR

A long polypeptide that folds into 7 segments that are imbedded in the membrane

What is a assumption of michaelis-menten kinetics

there is a single binding site for substrate

How does a competitive inhibitor affect Km and Vmax

Increases Km and does nothing to Vmax

How does a uncompetitive inhibitor affect Km and Vmax

Decreases Km and decreases Vmax

How does a noncompetitive inhibitor affect Km and Vmax

Does nothing to Vmax and decreases Vmax

Nonpolar amino acids

Great Adventures Make Valuing Life In Finite Ways Possible

Polar but neutral amino acids

Stoop To Your Caste Now Quitter

Polar but charged amino acids

Killing Red Haunts Dead- Ethereals-