Only one, just like you do.
Not normally. Cows have digestive systems that are designed to deal with grass as the food. However a LITTLE cereal grain in their diet will not harm them.
Cows are female bovines. Bulls are male bovines. Therefore they have the same digestive system!!
In their stomachs like we do.
At their mouths.
Oh yes, amphibians have digestive systems.
Yes, animals like cows and termites can effectively digest cellulose in their diet with the help of specialized microorganisms in their digestive systems.
Cows' feces is not grass because it is a byproduct of digestion. When cows eat grass, their digestive systems break down the plant material through fermentation and microbial action, extracting nutrients. The remaining waste, which includes undigested fibers, bacteria, and other substances, is excreted as feces. Thus, while grass is the input, the feces is a transformed output resulting from the complex digestive process.
Fibre content is higher in plants, so it takes longer to digest. This is why ruminants (cows and so on) have such complex digestive systems.
The pharynx is part of both the digestive and respiratory systems.
The digestive system provides usable nutrients for the other systems.
It doesn't.
The digestive system starts at the mouth.