Answer:
D) Three of the reaction steps in gluconeogenesis would have prohibitively large, positive free energies if they used glycolytic enzymes for their catalysis.
Explanation:
The glycolytic enzymes catalyze the conversion of glucose to pyruvate, while gluconeogenesis enzymes catalyze the formation of carbohydrates from pyruvate.
The exchange takes place in the millions of alveoli in the lungs and the capillaries that envelop them. As shown below, inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli. You can see more in wikipedia, or here: https://www.merckmanuals.com/home/lung-and-airway-disorders/biology-of-the-lungs-and-airways/exchanging-oxygen-and-carbon-dioxide
DNA is made of chemical building blocks called nucleotides. These building blocks are made of three parts: a phosphate group, a sugar group and one of four types of nitrogen bases. To form a strand of DNA, nucleotides are linked into chains, with the phosphate and sugar groups alternating.