Magda Rodriquez, age 15, of Nogales, Ariz., for her question:

WHERE IS THE JUGULAR VEIN?

Jugular vein is the name of each of four large veins that return blood to the heart from the head and neck. The veins received their name from the Latin word jugulus, which means collarbone.

There are two jugular veins on each side of the neck, known as the external and internal jugulars. '

The external jugulars lie close to the surface and carry blood from the outside parts of the head and neck to the heart. The internal jugulars lie deeper and carry blood from the deeper tissues of the neck and from the interior of the skull.

The internal jugular veins are much larger than the external,  and are the ones most commonly referred to. Opening an internal jugular vein usually proves fatal, because of the rapid loss of blood.