circu;atory system save my exams Flashcards
need for a ciruclatory system
constant supply of reactants for metabolism
oxygen and glucose directly from their surroundings, and the molecules can diffuse to all parts of the cell quickly due to short diffusion distances
mass transport system, for example
The digestive system is connected to the circulatory system
definition mass transport
bulk movement of gases or liquids in one direction, usually via a system of vessels and tubes
closed circulatory system
blood is pumped around the body and is always contained within a network of blood vessels
All vertebrates and many invertebrates have closed circulatory systems
systematic closed circulatory system
Humans have a closed double circulatory system: in one complete circuit of the body, blood passes through the heart (the pump) twice
The right side of the heart pumps blood deoxygenated blood to the lungs for gas exchange; this is the pulmonary circulatory system
Blood then returns to the left side of the heart, so that oxygenated blood can be pumped efficiently (at high pressure) around the body; this is the systemic circulatory system
pulmonary artery
carries deoxygenated blood away from the heart, towards the lungs
pulomary vein
carries oxygenated blood away from the lungs, towards the heart
coronary arteries
supply the heart with oxygenated blood
aorta
carries oxygenated blood out of the heart and to the rest of the body
vena cava
carries deoxygenated blood into the heart
renal artery
supplies the kidneys with oxygenated blood
renal vein
carries deoxygenated blood away from the kidneys, towards the heart
when do valves in the heart open
when the pressure of blood behind them is greater than the pressure in front of them
when do valves in the heart close
when the pressure of blood in front of them is greater than the pressure behind them
why are vealves important
keeping blood flowing forward in the right direction and stopping it flowing backwards. They are also important for maintaining the correct pressure in the chambers of the heart
atrioventricularvalve
The right atrium and right ventricle are separated by the atrioventricular valve,
pulmonary valve
The right ventricle and the pulmonary artery are separated