Vesicles are small cellular containers. They perform a variety of functions, such as helping to transport materials that an organism needs to survive and recycle waste materials. There are several ...

Capillaries are very tiny blood vessels — so small that a single red blood cell can barely fit through them. They help to connect your arteries and veins in addition to facilitating the exchange of ...

CD4+ T cells, or helper T cells, are one type of lymphocyte that helps coordinate the immune response against infection and disease. They interact and activate other cells in the immune system. The ...