34) An organism with a cell wall would most likely be unable to take in materials through A) osmosis B) active transport c) facilitated diffusion D) phagocytosis 35) Which electron carrier(s) function in the citric acid cycle? A) ADP and ATP B) the electron transport chain C) NAD+ only D) NADH and FADH2 36) What is the name of the thermodynamic barrier that must be overcome before products are formed in a spontaneous reaction? A) free energy B) entropy C) activation energy D) the equilibrium point 37) What is the function of the pigment molecules in a light-harvesting complex in the thylakoid membranes? A) They synthesize ATP from ADP and B) They absorb and transfer light energy to the reaction center chlorophyll C) They transfer electrons to NADP+ D) They split water and release oxygen from the reaction-center chlorophyll 38) How does a noncompetitive inhibitor decrease the rate of an enzyme-catalyzed reaction? A) by binding to the active site of the enzyme, thus preventing binding of the normal substrate B) by binding to an other region of the enzyme, thus changing the shape of the active site of the enzyme C) by binding to the substrate, thus changing its shape so that it no longer binds to the active site of the enzyme D) by decreasing the free-energy change of the reaction catalyzed by the enzyme 39) HIV is the virus that causes AIDS. In the mid-1990s, researchers discovered an enzyme in HIV called protease. Once the enzyme’s structure was known, researchers began looking for drugs that would fit into the active site and block it. If this strategy for stopping HIV infections were successful, it would be an example of what phenomenon? A) allosteric regulation B) competitive inhibition c) denaturation D) noncompetitive inhibition 40) A phospholipid bilayer with equal amounts of saturated and unsaturated fatty acids displays a specific permeability to glucose. What effect will increasing the proportion of unsaturated fatty acids in the bilayer have on the membrane’s permeability to glucose? A) Permeability to glucose will decrease. B) Permeability will decrease initially then increase as the bilayer fills with glucose. C) Permeability to glucose will stay the same D) Permeability to glucose will increase.
As you have not requested for a question in particular, so I
would like to answer the first four questions.
Answer 34) The correct answer is D)
phagocytosis. All the processes, except phagocytosis are
involved in material transport because of a presence of
semi-permeable membrane. Phagocytosis in particular, involves the
actin-based movement of cell membrane whenever its receptor
recognises a solid particle to be engulfed. This flexibility cannot
be achieved with a cell containing a cell wall.
Answer 35) The correct answer is D) NADH and
FADH2 . Acetyl CoA produced from pyruvate is acted upon by
removing electrons from it and which are furthur used to reduce
NAD+ with FAD as another electron carrier, together these produce
NADH and FADH2 which generates energy via ATP.
Answer 36) The correct answer is C) Activation
energy. Every reaction whether energy releasing
(spontaneous) or energy requiring, it has to have a energy input in
form of activation energy to make up for transition state, which is
highly unstable high energy state. For every chemical reaction that
requires breaking of bonds, it has to have a small energy input
prior to release of its own energy by breaking of bonds.
Answer 37) The correct answer is B) They absorb and
transfer light energy to reaction centre chlorophyll. The
pigments present in photo-systems absorb energy from sun, and pass
onto reaction centre, containing chlorophyll, which has a function
later to convert this light energy into chemical energy as ATP.
Hope this helps.