In 3-5 sentences, explain how the rate of photosynthesis or cellular respiration can be measured using products or reactants.

  by measuring the carbon dioxide (CO2) consumed during photosynthesis or generated during respiration

Explanation:   The method most commonly used to measure the rate of photosynthesis and cellular respiration is by determining the amount of carbon dioxide (CO2) consumption and production, respectively. Both consumption and production of CO2 can be indirectly measured by using bromothymol, which is a pH indicator. This indicator (bromothymol) turns blue in basic medium and yellow in acidic conditions.

the cell cycle is the final answer! : )

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements