BIOL 215 CWRU: Exam 3 UPDATED ACTUAL Exam Questions and CORRECT Answers

BIOL 215 CWRU: Exam 3 UPDATED
ACTUAL Exam Questions and CORRECT
Answers
Why do metabolic pathways comprise many small steps but not 1 big step? - CORRECT
ANSWER - many different pathways run from energy produced from prior reaction



Feedback Regulation of Enzyme Activity - CORRECT ANSWER - Metabolic pathways
regulated: intermediates/products 'feedback' to provide info.


Oxidation involves - CORRECT ANSWER - loss H+/e-; gain O



Reduction involves - CORRECT ANSWER - gain H+/e-; loss O



Disulfide bond formed under which conditions - CORRECT ANSWER - oxidizing
condition (loss H)


catabolism of triglycerides process - CORRECT ANSWER - hydrolysis to liberate
glycerol + 3 FAs glycerol -> glycolytic pathway


triglycerides is important for - CORRECT ANSWER - Hibernating/ migrating species



triglycerides is - CORRECT ANSWER - fat - important long term E-storage molecule (can
store more E than other macromolecules)


fats catabolized -> - CORRECT ANSWER - fatty acids and glycerol



Why do fats contain more extractable E? - CORRECT ANSWER - Because of their state
of reduction: contains long strings of -CH2 groups in hydrocarbon tails

,Why are fats ideal for storage? - CORRECT ANSWER - Nonpolar -> stored in anhydrous
form (w/out water)


B-oxidation is the pathway that catabolize_____ and removes _____ at a time - CORRECT
ANSWER - fatty acids, one acetyl (2C)


# cycles = #Carbons - 2


B-Oxidation occurs in _____ and generates _____ - CORRECT ANSWER - mitochondria,
peroxisomes and generates Acetyl CoA, reduced enzymes (NADH, FADH2)


glycogenolysis - CORRECT ANSWER - When E cell needs are not met and no incoming
source of glucose: glycogen phosphorylase triggers glycogen to release a G1P, shifting the
equilibrium towards G69 starting glycolysis


glycogenesis - CORRECT ANSWER - conversion of glucose -> glycogen; GP6 - GP1



if cells need energy and not have an incoming source of glucose - CORRECT ANSWER -
Trigger glycogenolysis -> activate glycogen phosphorylate -> push toward G6P production
(while G1P pile up)


trigger glycogenolysis -> activate glycogen phosphorylate -> push toward G6P production (while
G1P pile up) - CORRECT ANSWER - phosphoglucomutase



Energy needs of cell are NOT met and no glucose - CORRECT ANSWER -
Glycogenolysis triggered ---> catabolizes glycogen --> activation of glycogen phosphorlase -->
G1P liberated, converted to G6P which is catabolized via glycolysis


a build up of G-6-P and ATP indicate - CORRECT ANSWER - enough energy -> glucose
need to be stored -> tranfer to G1P glycogen synthesis pathway (glycogenesis) initiated

, what is glycogen - CORRECT ANSWER - where glucose is stored for our short-term
energy reserve


role of electron carrier in the cell - CORRECT ANSWER - transport protons and electron,
capable of doing the reducing/ oxidizing process


consumption of Cori cycle - CORRECT ANSWER - 6 ATP consume -> 2 ATP generate
(net 4 ATP) -> can't sustain forever


cori cycle process (step 1) - CORRECT ANSWER - muscle catabolize glycogen ->
pyruvate -> enter lactate fermentation


cori cycle process (step 2) - CORRECT ANSWER - lactate -> liver (=cardiovascular
system)liver convert lactate to glucose = gluconeogenesis


cori cycle process (step 3) - CORRECT ANSWER - glucose enter bloodstream



gluconeogenesis - CORRECT ANSWER - biosynthesis of glucose from noncarbohydrate
sources, important for blood glucose regulation


What is gluconeogenesis? - CORRECT ANSWER - biosynthesis of glucose from non-
carbohydrate sources (pyruvate, lactate, amino acid, glycerol)


where does gluconeogenesis occur? - CORRECT ANSWER - liver and kidney cell



Gluconeogenesis occurs when - CORRECT ANSWER - glucose level is low, cant deliver
O2 (strenuous activity, fasting, lack of carbohydrate diet)