BIOL 1P91 - Final Exam Prep Questions Well Elaborated Solutions

BIOL 1P91 - Final Exam Prep Questions Well Elaborated Solutions The source of energy that directly drives the synthesis of ATP during oxidative phosphorylation is - ANSWER ANSWER: H+ chemical gradient When conditions in a muscle become anaerobic during strenuous exercise, why is it necessary to convert pyruvate to lactate? - ANSWER ANSWER: To decrease NADH and Increase NAD+ What causes the rotation of the y sub unit of ATP synthase? How does the rotation promote ATP synthase? - ANSWER ANSWER: Movement of H+ through the contact site between c and a sub units. This allows y sub unit to rotate. Causes conformational change. The water necessary for photosynthesis? - ANSWER ANSWER: Provides the electrons to replace those lost in photosystem II In PSII, P680 differs from the pigment molecules in lightharvesting complex in that - ANSWER ANSWER: Transfers an excited electron to the primary electron acceptor The cyclic electron flow that occurs during photosystem ! produces: - ANSWER ANSWER: ATP During linear electron flow, the high-energy electron from P680* - ANSWER ANSWER: Eventually moves to NADP+ During the first phase of the Calvin cycle, carbon dioxide is incorporated into ribulose bisphosphate (RuBP) by - ANSWER ANSWER: rubisco The NADPH produced during the light reactions is necessary for? - ANSWER ANSWER: The reduction phase, which produces carbohydrates in the calvin cycle The majority of G3P produced during the reduction and carbohydrate production phase is used in making: - ANSWER ANSWER: RuBP to continue the cycle Photorespiration - ANSWER ANSWER: Is an inefficient way that plants can produce organic molecules by using O2 and releasing CO2 Photorespiration is avoided in c4 plants because: - ANSWER ANSWER: A & C - These plants separate the formation of a four- carbon molecule from the calvin cycle in different cells AND The enzyme PEP carboxylase functions to maintain high CO2 concentrations in bundle-sheath cells Plants commonly found in hot and dry climates that carry out carbon fixation at night are: - ANSWER ANSWER: CAM plants What are the two stages of photosynthesis? - ANSWER light reactions and calvin cycle What is the function of NADPH in the calvin cycle? - ANSWER ANSWER: Used during the reduction phase. It donates an electron to 1,3 BPG The benefit of second messengers in signal transduction pathways is - ANSWER ANSWER: an increase in the speed of a cellular response AND amplification of the signal Why did researchers initially believe the genetic material was protein? - ANSWER ANSWER: Proteins are biochemically more complex than DNA Which component is always different when comparing a nucleotide in a DNA strand to one in RNA? - ANSWER ANSWER: Pentose Sugar If the sequence of a segment of DNA is 5′-CGCAACTAC-3′, what is the appropriate sequence for the opposite strand? a. 5′-GCGTTGATG-3′ b. 3′-ATACCAGCA-5′ c. 5′-ATACCAGCA-3′ d. 3′-GCGTTGATG-5′ - ANSWER ANSWER: D - 2'- GCGTTGATG - 5' Which of the following statements of about the process of DNA is correct? - ANSWER ANSWER: New DNA molecules are composed of one strand of the old molecule and one new strand Mesleson and Stahl were able to demonstrate semiconservative replication in e. coli by: - ANSWER ANSWER: Using isotopes of nitrogen to label the DNA and determining the relationship of original and new DNA strands Which of the following happens in the cytosol? a) Glycolysis b) breakdown of pyruvate into an acetyl group c) citric acid cyle d)oxidative phosphorylation e) all of the above - ANSWER ANSWER: Glycolysis The net products of glycolysis are: a) 6 CO2 + 4 ATP, 2 NADH b) 2 pyruvate, 2 atp, 2 NADH c) 2 pyruvate, 4 ATP, 2 NADH d) 2 pyruvate, 2 GTP, and 2CO2 e) 2 CO2, 2 ATP & glucose - ANSWER ANSWER: b, 2 pyruvate, 2 atp, 2 NADH