Cirulatory System Flashcards
What are the two circuits in the cardiac system
Pulmonary and systemic
What is the pulmonary system
The system between the heart and the lungs
What is the pathway of blood in the pulmonary system
The deoxygenated blood travels from the right atrium, through the tricuspid valve into the right ventricle. Then the blood travels through the pulmonic semi lunar valve into the pulmonary artery which brings the blood to the lungs. Gas exchange occurs in the lungs where blood becomes oxygenated and gets rid of carbon dioxide. The pulmonary veins take the oxygenated blood back to the left atrium
What is the systemic system
Transports blood between your heart and your body
What is the pathway of blood in the systemic system
Oxygenated blood is pumped from the left atrium, through the bicuspid valve into the left ventricle. The it goes through the aortic semi lunar valve into the aorta. Arteries then transport blood to the rest of the body. Veins return the deoxygenated blood which is high in CO2 to the heart. The vena cava then returns the blood to the right atrium
What is the function of arteries
Carry blood away from the heart under high pressure
What is the function of the capillaries
Site of gas exchange between veins and arteries where O2 and CO2 diffuse to/from the muscles and lungs
What is the function of veins
Carry blood towards the heart under low pressure
What is the wall of the arteries
Thick walls-elastic layer, narrow lumen as the blood needs to go as fast as it can with no added pressure
What is the wall of the veins
Thin walls no elastic layer, wide lumen as blood travels slowly back to the heart. Have valves as they have to battle against gravity
What is the wall of the capillaries
Thin walls 1cell thick, tiny lumen. No elastic layer
Define heart rate
The number of times the heart beats in one minute
Define stroke volume
The volume of blood pumped from the heart during each contraction
Define cardiac output
The volume of blood pumped from the heart every minute
What is the role of blood cells in the circulatory system
Carry oxygen from the lungs to the rest of the body. Collects CO2 from body and brings it back to lungs
What is haemoglobin
A compound which binds with oxygen forming oxyhaemoglobin
What is vasoconstriction
The narrowing of blood vessels to areas of the body not involved in excercise
What is vasodilation
Expanding of blood vessels supplying blood to areas of the body involved in exercise
What is vasodilation
Expanding of blood vessels supplying blood to areas of the body involved in exercise
