Which organic compound essentials to cells is missing from the chart and what function does it serve in a cells

You exhale co2 which is produced during cellular respiration.  co2 combines with the water in your blood's plasma to make up one half of the body's most important buffer pair, carbonic acid.  the more physical activity you engage in, the more co2 your body is producing.  you can see this by putting some of the cabbage indicator in a glass and then blowing bubbles into it through a straw.  can you see a change in the color of the indicator?

At the current rate, a graph of carbon dioxide produced by fossil fuels over time would slope upward slope downward be horizontal be vertical

What is the name of the enzyme that forms at the start of transcription?