You eat pizza for lunch. Which step in the digestion process causes a chemical change in the pizza?
Your teeth bite the pizza and take a small piece into your mouth.

Your esophagus is a tube that moves the food from your mouth into your stomach.

Your teeth grind the pizza to smash it.

Your stomach mixes acid and enzymes with the food to break down protein in the pizza.

Pretty sure its the stomach but if there is a step which involves the salivary glands that should be the right one. if not, the stomach is the correct answer.

Explanation:

Acid in the Stomach can help breakdown food which is where the chemical change happens. The saliva also contains enzymes that break bonds in large molecules to form smaller molecules. (for the Salivary Gland)

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.

air enters through the nose, moves through the nasal cavity, the pharynx, the larynx, enters the trachea, moves through the bronchi andbronchioles till the alveoli.