Circulatory Flashcards
What are capillaries made of?
A single layer of epithelial cells
What are the types of blood vessels?
Arteries, veins, and capillaries
What do arteries and veins have?
Smooth muscle and connective tissue
What do valves prevent?
Back flow of blood
Where is the site of has exchange?
Alveoli
What happens during the diastole?
Blood flows from the veins into the heart chambers
What happens during systole?
Atria briefly contract and fill the ventricles with blood; ventricles contract and propel blood out
What does the sinoatrial node do?
Generates electrical signals that trigger the contraction if the atria
What causes heart attacks?
A coronary feeding in the heart is blocked
Where is blood pressure highest?
Arteries
Where can blood pressure drop to zero?
Veins
What keeps the blood moving back to the heart?
Muscle contractions, breathing, and one-way valves
How is blood pressure measured?
As systolic and diastolic pressures; measuring blood pressure can reveal cardiovascular problems
What happens when blood clots?
Blood clotting occurs when a blood vessel is injured. Platelets clump at the site and release thromboplastin, thromboplastin converts prothrombin to thrombin, and thrombin converts fibrinogen into fibrin, which causes a clot
