Introduction to the Cardiovascular System Flashcards
(31 cards)
Circulatory system
made up of the cardiovascular system and the lymphatic system
Cardiovascular system
made up of the arterial system, the heart, and the venous system
Pulmonary circulation
right side of heart → lungs → left side of heart
Systemic circulation
left side of heart → capillary beds of organs and tissues → right side of heart
Epicardium
(external): Evisceral serous pericardium
Myocardium
(middle): cardiac muscle layer
Endocardium
(internal): continuous with endothelium of blood vessels connecting with the heart
Conduction system of the heart
- Electrical impulse starts at SA node - atria contract
- Impulse travels to AV node at AV septum
- Impulse travels down left and right bundles in the IV septum
- Impulse spreads out to myocardium through conducting fibers - ventricles contract
What does each artery and its branches carry?
Oxygenated blood to a territory
Tunica intima
(internal): endothelium
Tunica media
(middle): smooth muscles and elastic fibres
Tunica adventitia
(external): connective tissue
sympathetic tone
background, low level contraction of smooth muscle in arterioles, due to tonic production of action potentials to arterioles by sympathetic nerves
anastomoses
where arteries connect to each other without an intervening capillary network. provides alternative routes for blood flow to supply cells distal to an arterial occlusion. each alternate route is called a collateral
end artery
the only arterial blood supply to a given area of the body
infarction
irreversible cell death due to hypoxia caused by loss of arterial blood supply. result of untreated occlusion of an end artery
what supplies blood to heart muscle?
left and right coronary arteries
what supplies blood to the upper limbs and head?
beaches of the arch of the aorta
what supplies blood to the thorax and abdomen?
descending aorta
what supplies blood to the pelvis and lower limbs?
the abdominal aorta which branches into the two common iliac arteries
what do veins do?
Drain deoxygenated blood from a territory
Venous blood is ‘pumped’ back towards the heart by:
venous valves, skeletal muscle pump, accompanying veins
Superficial veins
Smaller, run within the superficial fascia, drain into deep veins
Deep veins
Larger, run deep to the deep fascia in cavities, often in neurovascular bundles