What would happen, if HCl were not secreted in stomach.

If HCl would not be secreted then there will be following effects :

1.  Pepsinogen will not be activated and no digestion of proteins will take place in the stomach.

2. Germs may flourish in stomach in the absence of HCl.

3. Milk will not be coagulated, because prorennin is converted into rennin by the action of HCl.