The digestive system starts with the mouth where food is chewed. Food moves down the esophagus to the stomach. The stomach breaks down food with acids and enzymes. Nutrients are absorbed in the small intestine. Waste products are expelled through the large intestine and rectum.
The assassination of Archduke Franz Ferdinand of Austria. Alliances between major powers created a domino effect. Militarism and the arms race increased tensions. Nationalism and ethnic tensions within Europe. Imperial competition and colonial disputes.