Choose the molecule or process that is described by each phrase. Lactic acid is a byproduct of this process:
photosynthesis
anaerobic respiration
aerobic respiration

Geologists do not use carbon-based radiometric dating to determine the age of rocks. Carbon dating only works for objects that are younger than about 50,000 years, and most rocks of interest are older than that. Carbon dating is used by archeologists to date trees, plants, and animal remains; as well as human artifacts made from wood and leather; because these items are generally younger than 50,000 years. Carbon is found in different forms in the environment – mainly in the stable form of carbon-12 and the unstable form of carbon-14. Over time, carbon-14 decays radioactively and turns into nitrogen. A living organism takes in both carbon-12 and carbon-14 from the environment in the same relative proportion that they existed naturally. Once the organism dies, it stops replenishing its carbon supply, and the total carbon-14 content in the organism slowly disappears. Scientists can determine how long ago an organism died by measuring how much carbon-14 is left relative to the carbon-12.