CIRCULATION (Lectures 1–3) Flashcards
What are the 3 major functions of the circulatory system?
Transport, regulation, protection.
Which type of circulatory system do humans have?
Closed, double circulatory system.
Why is a closed circulatory system more efficient?
It maintains higher pressure and faster nutrient delivery.
What are the four chambers of the heart?
Right atrium, right ventricle, left atrium, left ventricle.
What prevents blood backflow in the heart?
Valves (tricuspid, mitral, pulmonary, aortic).
What is the pacemaker of the heart?
SA node.
What is the QRS complex on an ECG?
Ventricular depolarization.
What occurs during systole?
Heart chambers contract and pump blood.
.Which vessel type has valves?
veins
What is the function of capillaries?
Exchange of gases, nutrients, and waste.
What regulates blood entry into capillaries?
Precapillary sphincters
In which vessel is blood pressure the highest?
Arteries, especially the aorta.
What happens to velocity of blood in capillaries?
It slows down to allow exchange.
What is the primary function of the lymphatic system?
Maintain fluid balance and support immune function
What is elephantiasis?
Swelling caused by parasitic blockage of lymph vessels.
What causes a heart attack?
Blockage of coronary arteries.
What is a stroke?
Loss of blood flow to the brain.
What is atherosclerosis?
Build-up of plaques in arteries.
