Energy Conversion and Metabolic Compartmentation: Mitochondria and Chloroplasts
50 questions available
Questions
What is the fundamental mechanism shared by mitochondria, chloroplasts, and prokaryotes for harnessing energy, which links chemical bond-forming reactions to membrane transport processes?
View answer and explanationIn the structure of a mitochondrion, what is the name for the narrow gap between the inner boundary membrane and the outer membrane?
View answer and explanationWhat is the approximate net yield of ATP molecules from the complete oxidation of one molecule of glucose, starting with glycolysis and ending with oxidative phosphorylation?
View answer and explanationAccording to the text, what is the standard redox potential (in mV) of the NADH/NAD+ redox pair?
View answer and explanationThe human mitochondrial genome is described as having dense gene packing. What does this mean?
View answer and explanationIn the process of photosynthesis, what is the primary role of the antenna chlorophylls within a photosystem?
View answer and explanationWhat is the name of the protein kinase that, when retained on the mitochondrial outer membrane due to loss of membrane potential, initiates mitophagy?
View answer and explanationWhich complex in the mitochondrial respiratory chain is also an enzyme of the citric acid cycle and does NOT pump protons?
View answer and explanationIn the Z scheme of photosynthesis, which molecule serves as the final electron acceptor, receiving electrons from photosystem I?
View answer and explanationHow many tRNA molecules are required for mitochondrial protein synthesis in humans?
View answer and explanationWhich two-headed phospholipid is produced in and confined to mitochondrial membranes, where it is thought to support the high curvature of the cristae?
View answer and explanationIn the comparison between a mitochondrion and a chloroplast, where does the carbon-fixation cycle (Calvin cycle) take place?
View answer and explanationWhat is the approximate protein content by weight of the cristae membranes in mitochondria?
View answer and explanationThe Q cycle in cytochrome c reductase (Complex III) involves the transfer of electrons from one ubiquinol molecule. What is the net result of this process in terms of proton movement?
View answer and explanationThe inheritance of mitochondrial DNA in animals and plants is typically uniparental. From which parent is the mitochondrial DNA inherited?
View answer and explanationIn the carbon-fixation cycle, how many molecules of ATP and NADPH are consumed to produce one molecule of glyceraldehyde 3-phosphate from three molecules of CO2?
View answer and explanationWhat is the key structural difference between the inner membrane of a mitochondrion and the inner membrane of a chloroplast?
View answer and explanationThe human mitochondrial genetic code is described as a 'variant genetic code'. What does this mean?
View answer and explanationWhat is the primary function of the brown fat cells found in newborn human babies?
View answer and explanationIn the process of carbon fixation in C4 plants like corn, what is the initial molecule that CO2 is fixed into in the mesophyll cells?
View answer and explanationWhat is the approximate size, in daltons, of the pore created by porin molecules in the outer mitochondrial membrane?
View answer and explanationIn the respiratory chain, cytochrome c oxidase (Complex IV) reduces one molecule of molecular oxygen (O2) to two molecules of water. How many electrons and protons in total are required for this reaction?
View answer and explanationWhat is the approximate number of c subunits in the ATP synthase rotor ring of plant chloroplasts?
View answer and explanationWhich mobile electron carrier shuttles electrons between the cytochrome b6-f complex and photosystem I in the chloroplast thylakoid?
View answer and explanationWhat happens to the vast majority of the proteins found in mitochondria and chloroplasts?
View answer and explanationIn the process of mitochondrial fission, which type of protein assembles into helical oligomers to cause constriction and severance of the membranes?
View answer and explanationWhat is the key catalytic component within the special pair of Photosystem II that enables it to withdraw electrons from water?
View answer and explanationIn actively respiring liver mitochondria, the pH in the matrix is about half a pH unit higher than in the cytosol. If the cytosol is at pH 7, what is the approximate pH of the matrix?
View answer and explanationWhich component of the electrochemical proton gradient across the inner mitochondrial membrane makes the largest contribution to the proton-motive force?
View answer and explanationWhat is the name of the process in plants where Rubisco uses O2 instead of CO2, leading to a loss of fixed carbon without producing useful energy?
View answer and explanationIn the human mitochondrial genome, how many rRNA genes and tRNA genes are present?
View answer and explanationWhat structural arrangement do the mitochondrial ATP synthase complexes form in the cristae membranes that is thought to make ATP synthesis more efficient?
View answer and explanationWhat is the name of the soluble, copper-containing protein that transfers electrons from the cytochrome b6-f complex to photosystem I?
View answer and explanationWhich of the following is NOT a known function of mitochondria listed in Table 14-2?
View answer and explanationIn the comparison of mitochondrial genomes, which gene is NOT one of the five genes shared by all six genomes shown in Figure 14-58?
View answer and explanationApproximately what percentage of the total oxygen uptake in most cells is accounted for by the cytochrome c oxidase reaction?
View answer and explanationWhat is the function of the respiratory-chain supercomplex observed in the crista membrane?
View answer and explanationIn the evolution of life, which group of organisms is thought to have first produced atmospheric oxygen through the evolution of a water-splitting enzyme?
View answer and explanationWhat is the primary product of the carbon-fixation cycle that is exported from the chloroplast to the cytosol to produce sucrose and other metabolites?
View answer and explanationHow much more ATP can be made from a sugar molecule through complete oxidation in mitochondria compared to glycolysis alone?
View answer and explanationWhat is the special pair of chlorophylls in photosystem I called, based on its maximum light absorbance wavelength?
View answer and explanationA variant genetic code is a feature of mitochondria in many organisms. In mammals, what amino acid does the codon UGA code for, which is normally a stop codon?
View answer and explanationThe chloroplast is believed to have evolved from an endosymbiotic event between a eukaryotic cell and which type of prokaryotic organism?
View answer and explanationHow does the ADP/ATP carrier protein move ATP and ADP across the inner mitochondrial membrane?
View answer and explanationWhat is the primary distinguishing feature of C4 plants, such as corn, compared to C3 plants?
View answer and explanationWhat type of macromolecule forms the proton wires that allow for rapid proton movement through proteins like those in the respiratory chain?
View answer and explanationWhat is the approximate speed, in revolutions per minute, at which the ATP synthase rotor spins when driven by proton flow into the matrix?
View answer and explanationWhich component makes up the largest part of the proton-motive force across the chloroplast thylakoid membrane?
View answer and explanationIn the comparison of electron-conversion processes in Figure 14-4, what are the ultimate products of cell respiration in the mitochondrion?
View answer and explanationWhat is the name of the large protein assembly in the chloroplast thylakoid membrane that is functionally and structurally analogous to cytochrome c reductase (Complex III) in mitochondria?
View answer and explanation