Is mouth part of the gastrointestinal tract?

The mouth is part of the gastrointestinal tract. It is the first part of the digestive system and is responsible for the initial mechanical and chemical breakdown of food. The mouth contains the teeth, tongue, and salivary glands, which work together to break down food into smaller pieces and mix it with saliva to form a soft mass called a bolus. This bolus is then swallowed and travels down the esophagus to the stomach.