Circulatory system

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What type of circulatory system is the heart
The heart is a double circulatory system as is one complete circuit blood passes through heart twice. It is also a closed system
which Side of heart pumps what
right side pumps deoxygenated blood to lungs for gas exchange (pulmonary circulatory system)
left pumps oxygenated blood at high pressure to rest of body (systemic circulatory system)
function of heart  
hollow muscular organ which pumps blood around body
what are arteries  
blood vessels which carry oxygenated blood away from heart . have lots of muscle elastic tissue and narrow lumen to maintain high blood pressure
what are arterioles  
small arteries which branch from larger arteries and connect to capillaries
what are capillaries  
tiny blood vessels which connect arterioles and venues . pass directly past cells and tissues and perform gas exchange of substances
what are venules  
small vein which join capillaries to large veins
what are veins  
blood vessels which join deoxygenated blood back towards the heart . thin walls and have less muscle and elastic tissue and wider lumen . contain values to maintain blood flow back to heart
what does pulmonary artery do
carries deoxygenated blood from heart to lungs
what does pulmonary vein do
carries oxygenated blood from lungs to heart
what do coronary arteries do
supply heart with oxygenated blood and remove waste products . Located on surface of heart
what does aorta do
carries oxygenated blood out of heart and to rest of body
what does vena cava do
carries deoxygenated blood into heart
what does renal artery do
supplies kidneys with oxygenated blood
what does renal vein do
carries deoxygenated blood away from kidneys towards heart
What is the septum
Muscle tissue that separates left and right of heart
Separates left and right atria is inreratrial septum
separates left and right ventricle is inter-ventricular septum
why is septum important
to make sure that blood does not mix in heart chambers
what are valves in heart
muscle ’doors’ that open when blood pressure behind is greater than that in front and closes vice versa
importance of values  
make sure blood flows forward in right direction and maintaining correct pressure in chambers
Where are main values in heart
Tricuspid value between right atrium and left ventricle pulmonary valve between right ventricle and pulmonary artery
bicuspid valve between left atrium and left ventricle
aortic valve between left ventricle and aorta
Muscle thickness of valves
Muscle on left ventricle is significantly thicker than right as it has a larger distance to travel so thicker muscles have larger contraction and produce greater pressure
atria and ventricle wall thickness
atria walls a lot thinner as only have to pump blood to ventricles
what is cardiac cycle  
series of events that take place in one heart beat including muscle contraction and relaxation
what is systole and diastole
contraction is systole and relaxation is diastole
how does volume change in heart affect pressure
volume decrease , pressure increases
volume increase pressure decreases
process of atrial systole  
walls of atria contract
atrial volume decreases and pressure increases
pressure in atria greater than ventricles so atrioventricular valves open
blood forced into ventricles
ventricular systole  
Ventricular walls contract
ventricle volume decreases and pressure increases
pressure in ventricles rises above atria forcing AV to close
pressure in ventricle rises above aorta and pulmonary artery forcing semilunar valves to open so blood forced not arteries and out of heart
what is process of cardiac diastole
ventricles and atria are both relaxed
pressure in ventricles drops below that of aorta and pulmonary artery forcing semilunar valves to close
atria fill with blood as blood enters heart via vena cava and pulmonary vein
pressure in atria rises above that of ventricles forcing AV valves to open
blood flows passively into ventricles without atrial systole
cycle begins again
What does lines crossing over mean on cardiac cycle graph
Means that valves are open
Structure and function of capillaries
Have thin walls which are leaky which allow substance to leave blood and reach body tissue
form capillary beds which Important for exchange surfaces
Small lumen which forces blood to travel slower for efficent diffusion
walls made of endothelial cells and only one cell thick for shorter diffusion Rate
cells how wall have pores which allow blood plasma to leak out and form tissue fluid
function and structure of plasma
straw coloured liquid that constitutes around 55% of blood
95% water so good solvent o substances can dissolve in it and be transported around
how do plasma and tissue fluid link
as blood passes through capillaries , some plasma leaks out through gaps in walls of capillary to surrounding cells , resulting in formation of tissue fluid
tissue fluid and plasma similar but contains less proteins as to big to leave capillary pores so remain in blood
exchange os substance between cells ad blood occurs via tissue fluid
formation of tissue fluid
when blood is at arteriole end of capillary hydrostatic pressure great enough to push molecules out of capillary
protein remain in blood and creat a water potential gradient between capillary and tissue fluid so water moves out of capillaries into tissue fluid
at venue end of capillary less fluid is pushed out as pressure reduced
water potential gradient stabilises at end of arteriole so water begins to move back into capillaries.
what is oedema  
when blood pressure is high (hypertension) so pressure at arteriole end is even greater and pushes more fluid out of capillary and fluid accumilates around tissue
formation of lymph  
some tissue fluid enters lymph capillaries (separated from circulatory system and have closes ends and large pores to allow large molecules to pass)
large molecules that can not pass through capillaries enter lymph capillaries through small valves at start of lymphatic system
liquid moves along larger vessels of system by compression causes by body movement and valves stop back flow
lymph enter bloodstream through veins located close to heart
why is lymphatic system important
as plasma proteins that have escaped form blood retuned via Lymph capillaries and if not removed from Tissue fluid would lower water potential of tissue fluid and stop reabsorption of water into blood in the capillaries
why else is lymp system important  
as after digestion lipids are transported from intestines into bloodstream by lymph system
what is coronary heart disease
Any condition that interferes with coronary arteries which supply blood to heart muscles