AP BIOLOGY

Detailed explanation-1: -While gravity does assist, most of the work is done by peristalsis, a wave-like downward motion of the digestive tract that breaks food down as it transports it.

Detailed explanation-2: -Whether you use a hole in the ground or a fancy gold-plated toilet, on Earth, gravity pulls your waste down and away from you. For astronauts, “doing their duty” is a bit more complicated. Without gravity, any loose drops or dribbles could float out of the toilet.

Detailed explanation-3: -The digestive system breaks down food into nutrients such as carbohydrates, fats and proteins. They can then be absorbed into the bloodstream so the body can use them for energy, growth and repair. Unused materials are discarded as faeces (poo).