Bio-final exam 2
substrate-level phosphorylation accounts for approximately what percentage of the ATP fromed during glycolysis?
100%
in glycolysis, for each molecule of glucose oxidized to pyruvate
2 molecules of ATP are used and 4 molecules of ATP are produced
what wavelength of light in the figure is least effective in driving photosynthesis?
575nm
which is correct?
<I G= <I H - <I S
which line represents the bag with the highest initial concentration of sucrose?
A
when glucose monomers are joined together by glucosidic linkages to form a cellulose polymer, the changes in free energy, total energy, and entropy ar as follows:
+<I G, + <IH -<IS
when glucose monomers are joined together by glycosidic linkages to form a cellulose polymer, the changes in free energy, total energy, and entropy are as follows
+<I G, +<I H, - <I S
during a laboratory experiment, you discover that an enzyme-catalyzed has a <I G of -20 kcal/mol, If you double the amount of enzyme in the reaction, what will be the <I G for the new reaction?
-20 kcal/mol
what is the purpose of beta oxidation in respiration
breakdown of fatty acids
sucrose is a disaccharide, composed of the monosaccharides glucose and frutose. the hydrolysis of sucrose by the enzyme sucrase results in
breaking the bond between glucose and frutose and forming new bonds from the atoms of water
in general, a signal transmitted via phosphorylation of a series of proteins
brings a conformational change to each protein
which of the following is one of the ways that the membranes of winter wheat are able to remain fluid when it is extreamly cold?
by increasing the percentage of cholesterol molecules in the membrane
which line or lines represent (S) bags that contain a solution that is hypertonic at the end of the 60 min
B
which of the following membrane activities require energy from ATP hydrolysis?
NA+ ions moving out of the cell
what is the reducing agent in the following reaction? Pyruvate +NADH --> lactic acid +NAH+
NADH
which of the following is a true distinction between fermentation and cellular respiration?
NADH is oxidized by the electron transportation in respiration only
which of the following membrane activities require energy from ATP hydrolysis?
Na+ ions moving out of the cell
inside an active mitochondria, most electons follw whch pathwaY/
citric acid cycle --> NADH -->electron transport chain --> oxygen
increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
competive inhibition
when hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is the
creation of a proton gradient
which curve represents the behavior of an enzyme taken from a bacterium that lives in hot springs at temperatures of 70*C or higher
curve 3
which of the following types of reactions would decrease the entropy within a cell
dehydration reactions
if you examine side A after 3 days, you should find that
a decrease in the concentration of NaCl and a decrease in the water level
the solution in the U tube are separated by the selectively permeable membrane. The membrane is permeable to sodium chloride but not glucose. Side A is filled with a solution of .4M glucose and a .5M NaCl, and side B is filled with a solution containing .8M glucose and .4MNaCl. Initially, the volume in both arms is the same. if you examine side A after 3 days, you should find....
a decrease in the concentration of NaCl and a decrease in the water level
which of the following is an example of cooperativity?
a molecule binding at one unit of a tetramer allowing faster binding at each of the other three
which of the following intermediary metabolites enters the citric acid cycle and is formed, in part, by the removal of a carbon (CO2) from one molecule of pyruvate?
acetyl CoA
reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's
activation energy
the sodium/potassium works into
actively set up a higher concentration of Na+ outside of the cell and K+ inside of the cell
vampire cells contain a .001M intracellular solution; human blood is a .003 M solution. To prevent their cells from shriveling up when sucking blood, vampires transport a very large human protein, albumin, into their cells resulting in a high concentration of albumin intracellularly. How does this happen?
albumin is actively transported into the vampire cells through a transport protein
which of the following is considered an open system
an organism
succinate dehydrogenase catalyzes the conversion of succinate to fumerate. Fumerate is then converted into malonic acid by the enzyme malonic dehydrogenase. malonic acid binds to succinate dehydrogenase stopping the metabolic pathway. This is an example of
feedback inhibition
when Harry Potter uses a magic spell to make a car spontaneously appear out of thin air he is breaking the
first law of thermodynamics
which metabolic pathway is common to both cellular respiration and fermentation?
glycolysis
whch of the following occurs in the cytosol of a eukaryotic cell
glycolysis and fermentation
in the thylakoid membranes, what is the main rols of the pigment molecules?
harvest photons and transfer light energy to the reaction-center cholorphyll
a molecule that is phosphorylated
has an increased chemical reactivity; it is primed to do cellular work
in photosynthesis, which produces NADPH
light reactions alone
the molecule tha tfunctions as the reducing agent in a redox of oxidation-reducing reaction
loses electrons and loses energy
energy released by the electorn transport chain is used to pump H+ ions into which location?
mitochondrial intermembrane space
which of the following best describes the reaction?
negative <I G spontaneous
in photosynthesis, which requires glucose?
neither the light reactions nor the calvin cycle
energy released by the electron transport chain is used to pump H+ ions into which location?
nitochondrial intermembrane space
in thylakoids, protons travel through ATP synthase from the thylakoid space to the stroma, therefore the catalytic knobs of ATP synthase would be located
on the stroma side of the membrane
one function of both alcohol fermentation and lactic acid fermentation is to
oxidize NADH to NAD+
one function of both alcohol fermentation and lactic acid fermentation is to
oxidize the NADH to NAD+
the final electron acceptor of the electron transport chain that functions in aerobic oxidative phosphorylation is
oxygen
the final electron acceptor of the electron transport chain (ETC) in cellular respiration is ____. In the first ETC of photosynthesis it is _____. and in the second ETC of photosysthesis it is ____.
oxygen, P700, NADP+
when a cell releases a signal molecule into the environment and a number of cells in the immediate vicinity respone, this type of signaling is
paracrine signaling
which of the following processes includes all others?
passive transport
an inhibitor of which of the following could be used to block the release of calcium from the endoplasmic reticulum
phospholipase C and & IP3
which of the following types of molecules are the major structural components fo cell membrane
phospholipids and proteins
reduction of NADP+ occurs during
photosynthesis
which of the following statements best describes the relationship between photosynthesis and respiration
photosysthesis stores energy in complex organic molecules, while respiration releases it
which statement is TRUE?
plants do both cellular respiration and photosynthesis
the general name for an enzyme that transfers phosphate groups from ATP to a protein is
protein kinase
in mitochondria the exergonic redox reactions
provide the energy that establishes the proton gradient
which of the followingn would decrease entropy?
putting together a deck from ikea
one of the major categories of receptors in the plasma membrane reacts by forming dimers, adding phosphate groups, then activating relay proteins. Which type does this?
receptor tyrosine kinase
which of the following statements is (are) true about enzyme-catelyzed reactions?
the reaction is faster then the same reaction in the absence of the enzyme
which of the following sequences correctly represents the flow of electrons during photosynthesis?
H2O-->NADPH-->calvin cycle
whenever energy is transformed, there is always an increase in the
entropy of the universe
which of the following is true of enzymes?
enzyme increase the rate of chemical reaction by lowering activation energy barriers
the sodium potassium pump, pumps out 3 Na+ and pumps in 2 k+ the point of this is
establishes membrane potential, making the cell more negative than the extracellular environment
choose the pair of terms that correctly completes the sentence: catabolism is to anabolism as _____is to_____.
exergonic; energonic
glucose diffuses slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Using this information, which transport mechanism is most probably functionng in the intestinal cells?
facilitated diffusion
binding of a signaling molecule to which type of receptor leads directly to a change in distribution of ions on opposite sides of the membrane?
ligand-gated ion channel
where do the enzymatic reactions of the calvin cycle take place?
stroma of the choloplast
what is the primary function of the calvin cycle
synthesize simple sugars (G3P) from carbon dioxide
which of the following metabolic processes can occur without a net influx of energy from some other provess?
C6H12O6-->6CO2+6H2O
goblins use alcohol fermentation as their main source of energy (which explains their silly behavior) during this process
CO2 is produced and acetaldehyde is reduced by NADH into ethanol (ETOH)
when Dorothy threw water on the wicked witch of the west, the witch melted. The autopsy report stated the witch's cells actually exploded. therefore we can conclude
Dorothy threw pure water on the witch and the witch's cells were hypertonic to the water
during aerobic respiration, which of the following directly donates electrons to the electron transport chain at the lowest energy level
FADH2
santa's elves living in the north pole have a higher percentage of unsaturated fats in their cell membranes that elves living in the middle earth. the elves in middle earth have a higher percentage of cholesterol in their membranes. If an elf from ther north pole was visiting his cousin in middle earth during a heat wave
his cells will begin to have increased fluidity at a lower temperature compared to his middle earth cousins' cells
G-protein receptors become activated by
hydrophilic ligands
of the following molecules of the ECM, which is capable of transmitting signals between the ECM and the cytoskeleton?
integrins
lipid-soluble signal molecules, such as testosterone, activate
intracellular receptors
the activation site of an enzyme is the region that
is involved in the catalytic reaction of the enzyme
which of the following statements is correct about diffusion
it is a passive process in which molecules move from a region of higher concentration to a region of lower concentration
which of the following statements is correct about diffusion?
it is a passive process in which molecules move from a region of higher concentration to region of lower concentration
which of the following does not occur in the calvin cycle
release of oxygen
which process is most directly driven by light energy?
removal of electrons from chlorophyll molecules
reduction of oxygen which forms water occurs during
respiration
what kinds of molecules pass through a cell membrane most easily?
small and hydrophobic
where does the calvin cycle take place?
stroma of the chloroplast
which of the following statements correctly describes the normal tonicicty conditions for typical plant and animal cells?
the animal cell is in an isotonic solution and the plant cell is in a hypotonic solution
in photosynthesis, which requires Co2?
the calvin cycle alone
when a plant cell is submerged in a very hypotonic solution, what is likely to occur
the cell will become turgid
which statement describes the functioning of photosystem II?
the electron vacancies in P680 are filled by electrons derived from water
which of the following statements best represents the relationship between the light reactions and the Calvin cycle?
the light reactions provide ATP and NADPH to the calvin cycle, and the cycle returns ADP, Pi, and NADP+ to the light reactions
when electrons flow along the electron transport chains of mitochodria, which change occurs?
the pH of the matrix increases
the pH of the inner thylakoid space and the stroma has been measured in a plant cell. Which relationship would you expect to find?
the pH within the thylakoid space is lower then that of the stroma
in mitochondris, chemiosmosis pumps protons from the matrix into the intermembrane space, whereas in chloroplast, chemiosmosis pumps protons from
the stroma into the thylokoid space
what is the relationship between wavelength of light and the quantity of energy per photo
they are inversely related
what is the relationship between wavelength of light and the quantity of energy per photon?
they are inversely related
where do the electrons that are extracted from glucose go in aerobic cellular respiration?
they are shuttled to the electron transport chain in the mitochondria
the reaction-center cholorophyll of photosystem I is known as P700 because
this pigment is best at absorbing light with a wavelength of 700nm