Multiple choice

Are humans primary consumers of carbon dioxide or secondary consumers?

  1. primary

  2. secondary

  3. neither because humans release carbon dioxide

  4. both because humans use oxygen

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Humans are heterotrophs that consume organic carbon for energy and release carbon dioxide as a byproduct of cellular respiration. They do not consume carbon dioxide as a food source.