Answer the questions. 1. What are two jobs that smooth muscles do?

Smooth muscles are involuntary muscles found in various internal structures of the body. Here are two primary functions they perform: 1. **Control of Digestive Movements (Peristalsis):** - **Function:** Smooth muscles in the walls of the digestive tract (such as the esophagus, stomach, and intestines) contract and relax rhythmically to propel food and liquids through the digestive system. - **Example:** When you swallow, smooth muscles in the esophagus create waves of contractions that push the food down into the stomach. Similarly, in the intestines, these movements help in the mixing and absorption of nutrients. 2. **Regulation of Blood Vessel Diameter:** - **Function:** Smooth muscles in the walls of blood vessels, particularly the arteries and arterioles, regulate vascular resistance and blood flow by contracting or relaxing. - **Example:** When smooth muscles in arterial walls contract (a process called vasoconstriction), the diameter of the blood vessel narrows, increasing blood pressure. Conversely, when they relax (vasodilation), the vessel widens, decreasing blood pressure and allowing more blood to flow through. These functions are essential for maintaining various physiological processes such as digestion, blood circulation, and the distribution of nutrients and oxygen throughout the body.