Cardiovascular system Flashcards
What are acute responses?
The body’s immediate, short-term responses that last only for the duration of the activity and for a short time afterwards (recovery).
What are arteries?
Large, thick-walled blood vessels that carry blood away from the heart.
What are arterioles?
Small blood vessels that branch off from arteries and extend to capillaries.
What is arteriovenous oxygen difference (a-VO2 diff.)?
The difference between the concentration of oxygen in the arterial blood and the concentration of oxygen in the blood in the veins, measured in mL/100 mL of blood.
What are atria?
The two upper chambers of the heart that receive blood from the veins and pump it into the lower chambers (ventricles).
What is blood?
The fluid circulated by the heart around the body, consisting of plasma, red and white blood cells, and platelets.
What are blood vessels?
A transport network of arteries, capillaries, and veins that carries nutrients and waste around the body.
What are capillaries?
Tiny blood vessels in the cardiovascular system between the ends of the arterioles and the venules, where gas exchange occurs.
What is the cardiac cycle?
The movement of blood through the heart in one heartbeat, consisting of alternate systole and diastole of the atria and ventricles.
What is cardiac output (Q̇)?
The amount of blood ejected from the left ventricle of the heart per minute, calculated as Q̇ = SV × HR, measured in litres per minute (L/min).
What is the cardiovascular system?
The system that includes the heart and blood vessels, circulating blood throughout the body to deliver nutrients and remove waste.
What are coronary arteries?
The arteries that supply oxygen and nutrients to the cardiac muscle (heart).
What is deoxygenated blood?
Oxygen-poor (carbon dioxide-rich) blood.
What is diastole?
A relaxation of the heart muscle.
What is a heartbeat?
One contraction and relaxation of the heart muscle.
What is homeostasis?
A constant internal environment for optimal functioning of the body and its systems.
What is hyperthermia?
A rise in the body’s core temperature above 37.5–38.3 °C.
What is hypothermia?
A reduced core body temperature below 35 °C.
What is oxygenated blood?
Oxygen-rich blood.
What are precapillary sphincters?
One-way valves that control blood flow within capillaries.
What is pulmonary circulation?
The arteries and veins that feed blood from the heart to and from the lungs where blood is oxygenated.
What is steady state?
The state in which oxygen supply equals oxygen demand and energy is being supplied aerobically.
What is stroke volume (SV)?
The amount of blood ejected from the left ventricle with each heartbeat (contraction), measured in millilitres per beat (mL/beat).
What is systemic circulation?
The arteries and veins that feed blood from the heart to the whole body and back to the heart for reoxygenation.
What is systole?
A contraction of the heart muscle, specifically the ventricles.
What is systolic blood pressure?
The blood pressure recorded as blood is ejected during the contraction phase of the heart cycle, the higher of the two blood-pressure values.
What is thermoregulation?
The maintenance of core body temperature within a narrow range.
What is vasoconstriction?
A process whereby blood vessels narrow or constrict, causing a decrease in blood flow.
What is vasodilation?
A process whereby blood vessels increase their diameter, causing an increase in blood flow.
What are veins?
Blood vessels that carry deoxygenated blood and waste products from the body’s cells back to the heart.
What is venous pooling?
A collection of blood in the leg veins when high-intensity activity stops too suddenly.
What are ventricles?
The two lower chambers of the heart that receive blood from the atria and pump it to the lungs (right ventricle) and to the body (left ventricle).
