CH10,13,14 HW Flashcards
(23 cards)
Which of the following best describes a cholesterol molecule?
Is a type of sphingolipid
Is highly polar and soluble in water
Is made of all hydrogens and carbons
Has a steroid nucleus, an alkyl chain, and an alcohol group
Has a steroid nucleus, an alkyl chain, and an alcohol group
Which of the following is FALSE regarding trans fatty acids?
Trans fatty acids have been found to raise LDL levels in the body.
They are formed from cis- fatty acids
A trans fatty acid packs together more tightly than the same fatty acid in the cis configuration
Trans fatty acids have been found to raise HDL levels in the body.
Trans fatty acids are not “kinked” in their structure
Trans fatty acids have been found to raise HDL levels in the body.
Which of the following is an example of a phospholipid that contains an ether-linked alkene? Phosphatidylcholine Sphingolipids Platelet Activating Factor Plasmalogen Triacylglycerol
Plasmalogen
Which of the following is a precursor for Vitamin D in the skin? trans-retinal prednisone cholesterol cis-retinal
cholesterol
Incorporation of a cis-double bond into a fatty acid chain will \_\_\_\_\_\_\_\_\_\_\_\_\_\_ its melting temperature. not alter decrease No answer text provided. increase
decrease
A fatty acid designated ω-3 ________.
Has a double bond three carbons from the alpha-carbon
Has three double bonds
Has a double bond three carbons from the end of the chain
Is saturated
Has a double bond three carbons from the end of the chain
Which of the following is a storage lipid for energy? Cholesterol Plasmalogen Platelet Activating Factor Vitamin D Triacylglycerol
Triacylglycerol
Which of the following would contain a single sugar residue? A cerebroside A globoside A sphingosine A ceramide A ganglioside
A cerebroside
A biochemical reaction will proceed from reactants to products if \_\_\_\_\_\_\_\_. ΔG < 0 ΔG > 0 ΔG = 0 ΔH > 0
ΔG < 0
Of the following, which is the most highly reduced compound (can derive the most energy from oxidation)? water carbon dioxide a monosaccharide an alcohol a fatty acid
a fatty acid
Which of the following is a common redox cofactor used in biosynthetic pathways like fatty acid biosynthesis? NAD+/NADH + H+ FMN FAD/FADH2 NADP+/NADPH
NADP+/NADPH
Which of the following common biochemical reactions results in a loss of electrons by one reactant and a gain of electrons by another? oxidation/reduction reactions internal rearrangements none of the answers here is true free radical reactions group transfer reactions
oxidation/reduction reactions
Which of the following is true of the hydrolysis of ATP under standard conditions?
It is not favored under standard conditions
The products of hydrolysis (ADP + Pi) are less stable than the reactant (ATP).
The hydrolysis of ATP results in products that have more favorable resonance stabilization.
The hydrolysis of ATP results in a standard free energy change that is large and positive
More than one answer here is true
The hydrolysis of ATP results in products that have more favorable resonance stabilization.
If the ΔG’º of a reaction of A->B is -40 kJ/mol, under standard conditions the reaction:
will never reach equilibrium
is at equilibrium
will proceed spontaneously from left to right
will proceed at a rapid rate
will not occur spontaneously
will proceed spontaneously from left to right
If a reaction is at equilibrium, what is the free energy change?
It is always negative.
It equals zero.
It is always positive.
It could be either positive or negative depending on the reaction.
It equals zero.
Glycolysis is regulated primarily by ________.
Three strongly exergonic, non-equilibrium reactions
Allosteric effectors of pyruvate kinase
Three strongly endergonic, non-equilibrium reactions
The availability of glucose-6-phosphate
Three strongly exergonic, non-equilibrium reactions
n order for glycogen to be broken down to glucose for use in the glycolytic pathway, it must first be directly converted to \_\_\_\_\_\_\_\_\_\_\_\_\_. Pyruvate Fructose 6-phosphate 2,3 Bisphosphoglycerate Glucose 6-phosphate Glucose 1-phosphate
Glucose 1-phosphate
Which of the following enzymes breaks down maltotriose and other oligosaccharides in the intestine? lactase alpha glucosidase maltase alpha dextrinase sucrase
alpha glucosidase
Which of the following GLUT transporters has a very low Km for its substrate, glucose
No answer text provided.
GLUT2
GLUT1
GLUT4
GLUT3
More than one transporter listed here has a low Km for glucose
More than one transporter listed here has a low Km for glucose
Which of the following is responsible for exporting unmodified glucose from the endoplasmic reticulum lumen to the cytosol of a liver cell? T2 transporter G6P transporter GLUT2 T3 transporter Glucose 6- phosphatase
T2 transporter
An intermediate metabolite found in gluconeogenesis and not glycolysis is \_\_\_\_\_\_\_\_\_\_\_. fructose 1,6 bisphosphate oxaloacetate glyceraldehyde-3-phosphate 2-phosphoglycerate phosphoenolpyruvate
oxaloacetate
When yeast produce ethanol from glucose, the reduction of acetaldehyde to ethanol directly:
generates ATP
regenerates NAD+
produces NADH
produces FADH
regenerates NAD+
The pentose phosphate pathway provides \_\_\_\_\_\_\_\_ for reductive biosynthesis and \_\_\_\_\_\_\_\_ for nucleic acid biosynthesis. NADH; ribose-5-phosphate FADH2; ribulose-5-phosphate NADPH; ribose-5-phosphate FAD; ribose-5-phosphate NAD+; ribulose-5-phosphate
NADPH; ribose-5-phosphate
