Why are bacteria abundant in the large intestines but not in the stomach?
A) Food enters the stomach first and does not spend much time there.
B) The intestine is much warmer and moister, encouraging bacterial growth.
C) The stomach wall contains so much lymphoid tissue that it destroys all bacteria there.
D) Secretions of parietal cells kill bacteria in the stomach.

Question

Quizplus · Accepted Answer

The stomach has a low pH due to secretions of hydrochloric acid by parietal cells, which kills most bacteria that enter the stomach. However, in the large intestine, which is warmer and more moist, bacteria can thrive on the undigested food and produce beneficial compounds such as vitamin K and B vitamins.

Why Are Bacteria Abundant in the Large Intestines but Not