Junior Cert Science - BIOLOGY - The Circulatory Systemheart1a.jpg

Gap-fill exercise

  
Fill in all the gaps, then press "Check" to check your answers.
You have eight minutes to complete this exercise. Good luck!
The circulatory system is made up of the , blood and blood vessels. Blood is composed of , red blood cells, white blood cells and platelets. Plasma transports dissolved food, wastes, antibodies, hormones and around the body. Red blood cells contain which transports oxygen from the to all parts of the body. White blood cells fight . Platelets clot the blood at . carry blood away from the heart. carry blood to the heart. Veins contain which prevent the backflow of blood. are very thin blood vessels with very thin walls that allow oxygen and food pass in and out of the bloodstream. Capillaries link arteries to veins. The heart pumps around the body. Blood flows into the atria and out of the . Blood enters the heart through the cava and the pulmonary . Blood leaves the heart through the and the pulmonary . The in the arteries is caused by the heart beating. The pulse rate increases during because the body needs more and food.