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You have forecast the following 24-hour, person-trip, production-attraction (PA) matrices for home-based (HB) and non-home-based (NHB) trip purposes.  Calculate the total number of HB and NHB trips between each zonal pair and in each direction (i.e., originating in zone 1 and destined to 2, originating in 2 and destined to 1, and so on.) over a 24-hour period.  Make reasonable assumptions as needed. NOTE: In your answer space you can insert a 4X4 table and provide your results

Which one of the following enzymes possesses a phosphorylated histidine residue in its active site?

Which of the following best explains how the presence of citrate simultaneously promotes fatty acid synthesis and inhibits glycolysis?

During the larval development of Drosophila melanogaster, energy production and redox balance are vital for sustaining rapid growth. The metabolic machinery that supports this growth includes two enzymes with overlapping functions: lactate dehydrogenase (LDH) and cytosolic glycerol-3-phosphate dehydrogenase (GPDH1). These enzymes help maintain glycolytic flux and redox balance under aerobic conditions, reminiscent of the Warburg effect observed in tumor cells. LDH typically catalyzes the interconversion of pyruvate and lactate, simultaneously oxidizing NADH to regenerate NAD⁺, which is required to sustain glycolysis. Interestingly, Drosophila larvae lacking LDH were able to maintain normal developmental timing and body size. Metabolomic analysis of these mutants revealed a significant increase in glycerol-3-phosphate (G3P), suggesting compensation through the GPDH1 pathway. GPDH1 catalyzes the reduction of dihydroxyacetone phosphate (DHAP) to G3P using NADH, also regenerating NAD⁺. However, when both LDH and GPDH1 were genetically ablated, the double mutants exhibited developmental delay, impaired glycolysis, elevated NADH/NAD⁺ ratios, and eventual lethality. This synthetic lethality highlights the compensatory and cooperative roles of LDH and GPDH1 in carbohydrate metabolism. The glycerol phosphate shuttle also plays a role in transferring reducing equivalents into mitochondria via mitochondrial GPDH, linking cytosolic NADH oxidation to mitochondrial FAD reduction. The interplay between these enzymes underscores how redundancy and flexibility in metabolic pathways are essential for developmental robustness in metabolically active tissues. A researcher creates a Drosophila mutant with overexpression of mitochondrial GPDH. Which of the following is the most likely outcome of this genetic alteration?

A toxin specifically inhibits electron transfer from NADH to FMN at Complex I of the mitochondrial electron transport chain. Which of the following is the most immediate metabolic consequence of this inhibition?

Which of the following best explains why substrate-level phosphorylation during glycolysis can still proceed efficiently even when intracellular ATP concentrations are elevated?  

Which of the following correctly explains the role of transketolase in the non-oxidative phase of the pentose phosphate pathway?  

In hepatocytes, which of the following scenarios would most strongly favor the initiation and sustained flux through gluconeogenesis?

Under anaerobic conditions, some organisms convert pyruvate into ethanol through a two-step enzymatic pathway. In the first step, pyruvate decarboxylase, an enzyme requiring thiamine pyrophosphate (TPP) and Mg²⁺, catalyzes the decarboxylation of pyruvate to acetaldehyde, releasing CO₂. In the second step, alcohol dehydrogenase reduces acetaldehyde to ethanol, using NADH as a reducing agent, which is oxidized to NAD⁺. This regeneration of NAD⁺ is essential for maintaining glycolytic flux under oxygen-limited conditions. The overall process allows for the recycling of NAD⁺ required by glyceraldehyde 3-phosphate dehydrogenase in glycolysis, thereby enabling continued ATP production in the absence of oxygen. This pathway is most commonly observed in yeast and some facultative anaerobes. If a yeast strain is genetically modified to lack functional pyruvate decarboxylase, which of the following outcomes is most likely?

This is a two-part question. Part (a):  If a transfer between the two divisions is arranged at a price (on 3,000 units of super chips) of $40, the Chip division’s profits will (a) increase or decrease by (b) $_______________________ compared to its prior month. Select the answer for (a) below.