Complete the statements below to find out how the organs of the circulatory system
work together to do a specific task. Choose the best word in the box.

arteries capillaries blood vessels heart plasma
platelets red blood cells white blood cells valves veins

When the (1) ____________________ pumps blood, it produces pressure that pushes
blood to the body. The (2) ____________________ serve as the passageways of blood to all
parts of the body. The blood travels away from the heart in vessels called (3)
____________________. The blood returns to the heart in the vessels called (4)
____________________. To stop blood from flowing backwards, flexible flaps of tissues called (5)
____________________ are found in the heart and veins. Arteries and veins are connected by
tiny, thin-walled vessels called (6) ____________________. These very small vessels are in close
contact with the tissues and cells of the body. The exchange of nutrients, oxygen, carbon dioxide
and waste happened through the walls of these small vessels.
The blood is made up of the liquid part called (7) _______________ that carries the three
solid composition or cells of the blood. The (8) ____________________ carry oxygen and
nutrients to the cells and also collect waste. The (9) _____________________ fight infections and
the (10) ____________________ make blood clot to stop the body from bleeding