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.
Roundworms (Toxocara canis, Toxascaris leonine) are the most common types of intestinal parasites seen in dogs and are especially common in puppies. Adult roundworms live in the intestinal tracts of their hosts, consuming that host's food.