Final answer:
Leavening agents are substances that release air-like gases in dough or batter, causing them to rise and become fluffy and porous.
Step-by-step explanation:
The substances that allow dough or batter to rise during baking by releasing air-like gases are called leavening agents. These agents produce carbon dioxide gas and create air pockets within the mixture, resulting in a fluffy and porous structure in the final product. Examples of leavening agents include baking soda, baking powder, and yeast.
Learn more about Leavening agents in baking