Smooth muscle cells are contractile and will contract from many different agents such as hormones travelling in the blood and neurotransmitters from the autonomic nervous system. The smooth muscle cells are coupled together so that when one cell contracts, the contraction is relayed to the next. This contractile ability is important in the vascular system as it helps regulate blood pressure by changing the size of the lumen of the vessel. <span>This contractile feature also enables the movement of food through the digestive tract. Rhythmic contractions of smooth muscle cells, called peristalsis, moves the food along. </span> I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
states that each rock layer is older than the one above it. So, the relative age of the rock or fossil in the rock or fossil in the rock is older if it is farther down in the rock layers.