Answer to Question 1
Baking powder and baking soda were used. Baking powder is a mixture of baking soda and agents that provide acid; they react when a liquid is added and again when it is exposed to heat. It is therefore called double-acting baking powder. Baking soda will need a liquid added as well as an acid present in the mixture so it can give off carbon dioxide. These both react quickly to provide leaveninghence the name quick bread.
Answer to Question 2
To avoid excess gluten production. Excess gluten formation results in excess carbon dioxide being trapped inside gluten walls; carbon dioxide tries to escape but cannot. This results in a peaked top and interior tunneling.
Energy coupling in mechanical and chemical processes
Effect of the chemical environment on pKa
Discrimination between p and ppi and chemical structure of ATP
Chemical Mediators of Inflammation
The chemical structure of the water molecule facilitates life
Chemical bookkeeping