Cardiovascular system Flashcards
What blood is carried in the pulmonary circuit?
Deoxygenated blood
What blood is carried in the systemic circuit?
Oxygenated blood
What is the function of the pericardium?
-protect the heart
-anchor the heart in position
-prevent overfilling the heart with blood
-fluid within the pericardial cavity provides a friction free environment
What are the two layers of the sereous layer of the pericardium?
-parietal-outer
-visceral-inner
Structure of endocadium?
-squamous epithelium
-continuous endothelial linings of blood vessels
-inner layer
Function of the epicardium?
supports blood vessels and nerves
what are the three layers of the heart?
epicardium, myocardium, endocardium
right ventricle pumps blood to…..
left ventricle pumps blood to….
-lungs
-body
What pressure requirements does the pulmonary circulation and systemic circulation need?
PC- lower pressure
SC- higher pressure
Describe the lub dub sound of the heart
lub-closure of AV valves
dub-closure of SL valves
What are the three layers of arteries and vein walls?
-tunica intima
-tunica media
-tunica externa
Describe the structure of the tunica externa
-connective tissue
-rich on collagen
Describe the structure of the tunica media
-smooth muscle and elastic fibres
Describe the structure of the tunica intima
simple squamous epithelia
Describe the structure and function of elastic arteries
-thick walled
-lots of elastic tissue
-allows for expansion and contraction causing blood to flow smoothly
Describe the structure and function of muscular arteries
-smaller and they branch from elastic arteries
-distribute blood to body
-more muscular tunica media allows blood flow to be controlled
What is the structure of arterioles?
-smooth muscle/media surrounding endothelium
-held by outer layer of collagen fibres
What is the function of arterioles?
-smooth muscle allows regulation of blood flow to cappilaries
-vasoconstriction when smooth muscle contracts, vessel lumen is smaller, less blood flow
-vasodilation-relaxed, lumen is larger, more blood flow
Structure and function of cappilaries
-thin wall-just tunica intima
-provide access to all cells of the body
-exchange site
-slower blood flow, exchange can occur, large surface area
What is the structure of Veins and Venules?
-venules-cappilaries joining together
-veins-venules joined together
-pressure in veins is lower than arteries because vein walls are thinner
what causes a pulse?
-result of left ventricle contracting - systolic pressure
Name some different pulse sites
-superficial temporal artery
-facial artery
-common cartoid artery
-brachial artery
-radial artery
-femoral artery
-popliteal artery
-posterior tibial artery
-dorsalis pedis artery
What are the two branches of the coronary artery?
-anterior interventricular artery
-circumflex artery
What are the two branches of the right coronary artery?
-right marginal artery
-posterior interventricular artery
Describe the process of the coronary circulation
-venous blood collected by cardiac veins
-joined to form the coronary sinus-empties blood into RA
-several anterior cardiac vein also empty into RA
Name the three large tributaries of the coronary sinus
-great cardiac vein
-middle cardiac vein
-small cardiac vein
Describe the events that cause an increase in heart rate during excersise
-Chemoreceptors detect an increase in CO2 concentration in the blood
-impulses sent to the cardioaccelerator centre in the medulla
-more impulses sent to the SAN via the SNS
-More impulses from the SAN
-increased heart rate
