When the stomach is empty, the walls are folded into rugae (stomach folds), which allows the stomach to expand as more food fills it.
In the stomach, food undergoes chemical and mechanical digestion. The peristaltic contractions churn the bolus, which mixes with strong digestive juices that the stomach lining secrete. The stomach walls contain three layers of smooth muscle arranged in longitudinal, circular, and oblique rows. These muscles allow the stomach to squeeze and churn the food during mechanical digestion.
Answer:
Bright light
Explanation:
This is why when you stay long in a dark room, then move suddenly into light, your instinctive response is to squint. This automatic response is for the eye to reduce the amount of light entering the eye, to avoid eye damage. This gives time for the iris to respond and reduces the size of the pupil. When the iris relaxes and reduces the size of the pupil, then your eye acclimatizes to the bright light and the squinting stops.
