I believe I am on the right track and with this answer
Stomach- Secretes HCl from glandular tissue in order to provide the optimum pH for Protease, the enzyme in the stomach which breaks down proteins into amino acids (I believe pepsin is also present). The stomach also has muscular tissue which churns the stomach contents to increase rate of reaction between the protease and proteins.
Small intestine- Bile is produced by the liver and stored in the gall bladder. It's released into the small intestine via the bile duct and neutralises the stomach acid (HCl), providing optimum conditions for the enzyme Lipase (slightly alkaline). Bile also emulsifies fats, giving them a larger surface area, making Lipase react faster with the lipids. The small intestine also has a large surface area for absorption of products of digestion, as well as having villi to increase the surface area to