Question

which plays both a role in physical and chemical digestion?
teeth
saliva
gall bladder
villi

Explanation:

• Teeth: Only involved in physical digestion (chewing).
• Saliva: Contains enzymes (chemical digestion) and also helps moisten food (physical aspect).
• Gall bladder: Stores bile (chemical digestion - emulsifies fats), no physical role.
• Villi: Involved in absorption, not digestion.

Answer:

saliva