Usually four, though rarely, it can vary.
the veins are blue.
blue color
Veins, arteries or valves
Tubes connected to the heart are called arteries and veins.
Of course Dummies, How can you breathe if they weren't connected?
technically yes they are, but some are joined onto other veins
The tubes connected to the heart are the arteries and veins. Veins carry blood to the heart, and arteries carry blood away from the heart.
There are 72,000 MAJOR VEINS in a regular human body.
Your veins are running all throughout your body with blood running through them. And all the veins are connected the the heart.
There are more veins by far.
pulmonary vein