Circulatory Responses to Exercise Flashcards
List the 3 main purposes of the cardiovascular system. (homeostasis)
Transport of O2 to tissues and removal of wastes. Transport of nutrients. Regulation of body temperature.
What is preload?
initial stretching of the cardiac muscle cells prior to contraction
What is afterload?
force or load against which the heart has to contract to eject the blood.
Explain pulmonary circulation.
right side of the heart pumps blood through the pulmonary circulation which is low pressure.
Explain systematic circulation.
left side of the heart delivers blood to the systemic circulation which is high pressure.
Does each side of the heart have equal cardiac output?
Yes, but different pressures.
What are the arteries?
large vessels that carry arterialized blood away from the heart. Systemic arteries are fully oxygenated blood.
What are the veins?
the blood vessels that accept blood from the venues and bring it back to the heart. For pulmonary system, veins bring back oxygenated blood to the heart.
What are arterioles?
a small branch of an artery that communicates with a capillary network
What are capillaries?
microscopic blood vessels that connect arterioles and venules. portion of vascular system where blood/tissue gas exchange occurs.
What are the venules?
small blood vessels carrying capillary blood to veins.
Describe the basic anatomy of the heart (chambers).
Heart is comprised of four chambers and is often described as two pumps in one – right atrium and right ventricle form the right pump/left atrium and left ventricle make the left pump.
What is the difference between right and left side of the heart?
There is never blood without oxygen, just much lower. Right side is “deoxygenated” blood and left side is “oxygenated” blood.
What do Atria do and where are they located?
Atria are located on top and collect blood.
What do ventricles do and where are they located?
Ventricles are on the bottom and eject blood.
List the 4 valves of the heart.
Tricuspid valve, semilunar valve, bicuspid valve and aortic valve.
Describe the cardiac cycle.
the cardiac cycle is all events between consecutive heartbeats.
List the 3 layers of cardiac muscle.
Epicardium, myocardium, endocardium.
What is the inner layer of cardiac muscle?
endocardium
What is the middle layer of cardiac muscle?
myocardium
What is the outer layer of cardiac muscle?
epicardium
What is the ventricular contraction phase called?
Systole. Ventricles contract, atria relax.
What is ventricular relaxation phase called?
Diastole. Atria contract, ventricles relax.
How long does systole and diastole last during rest and heavy exercise?
During rest, systole lasts 0.3 s and diastole lasts 0.5 s. During exercise, systole lasts 0.2 s and diastole lasts 0.13 s. This can be explained because during exercise the cardiac cycle is much shorter due to the large increase in heart rate so diastole is shortened.
What is the average blood pressure during a cardiac cycle called? What is the formula?
Mean Arterial Pressure (MAP). MAP = DBP + 0.33 x (pulse pressure)
How do you calculate pulse pressure?
Systolic blood pressure - diastolic blood pressure