the heart Flashcards
substances that are transported in the blood
oxygen, carbon dioxide, glucose, urea, antibodies and hormones
where is oxygen carried
in the red blood cells
where are dissolved substances carried
in the plasma
what do to heart chambers consist of
two atria and two ventricles
how blood enters and leaves the body
blood enters the heart through the atria. blood from two vena cavae enters the right atrium. blood from the pulmonary veins enters the left atrium. the atria fill, followed by the ventricles. blood is prevented from flowing back into the atria by heart valves.
Blood leaves the heart in the body’s main artery - the aorta - from the left side, and the pulmonary artery, from the right.
what type of circulation do humans have
a double circulatory system
Q: the pulmonary circulation transports blood to the lungs. at the lungs:
oxygen diffuses into the blood from the alveoli - the blood becomes oxygenated
carbon dioxide diffuses from the blood into the lungs
arteries
carry blood away from the heart
veins
carry blood to the heart
structure of veins
thin walls, wide lumen and contain valves
structure of arteries
have thick muscular and elastic walls, narrow lumen and no valves
capillaries
enable the exchange of substances between the blood and surrounding tissues
structure of capillaries
thin walls, tiny
