Answer:
Change their external environment is the correct answer.
They evolved during the Cambrian explosion.
Answer:
After you eat it takes about six to eight hours for food to pass thorough your stomach and small intestine. Food then enters your large intestine (colon) for further digestion absorption for water and finally elimination of undigested food. It takes 36 hours for food to move through the entire colon.
Explanation:
Cellular respiration uses energy in glucose to make ATP. Aerobic (“oxygen-using”) respirationoccurs in three stages: glycolysis, the Krebs cycle, and electron transport. In glycolysis, glucose is split into two molecules of pyruvate.