Supply and demand. The coronary arteries regulate the supply of blood to your heart muscle depending on how much oxygen your heart needs at the time, as indicated by: The number of times your heart beats per minute (heart rate). Your blood pressure. The force of your heart's contractions.
The pinworm is the most common roundworm in the United States. It is small and threadlike and infests many more children than adults. The ascaris roundworm thrives in the intestinal tract of mammals and can range in length from six to thirteen inches.
Ascariasis, or roundworm, is an intestinal parasitic infection and is part of a family of parasites known as the soil-transmitted helminths. It affects more than 1 billion people worldwide.