Heart Flashcards
Why do singular-cell organisms not need a circulatory system
The organisms can easily diffuse oxygen and glucose from their surroundings to all parts of the cells due to short diffusion distances
Mass transport
The bulk movement of gases or liquids in one direction ( Oxygen and glucose etc )
What type of system is humans circulatory system
Double closed
What side of the heart deals with deoxygenated blood
Right side
What side of the heart deals with oxygenated blood
Left side
Route of deoxygenated blood
Vena cava, Right atrium, Right atrioventricular valve, Right ventricle, Right semi-lunar valve, pulmonary artery, lungs
Route of oxygenated blood
Pulmonary vein, left atrium, left atrioventricular valve, left ventricle, left semi-lunar valve, aorta, body
Arteries
Carry high pressure oxygenated blood away from the heart. Have thick and elastic walls to withstand the pressure of the blood. They also have a narrow lumen to withstand blood pressure
Veins
Carry low pressure deoxygenated blood towards the heart. Have thin walls and a wide lumen. They also have valves to prevent the backflow of blood
Where is the pacemaker in the heart
Right atrium
Coronary arteries
Supply the heart with blood as it is a respiring muscle that undergoes aerobic respiration so needs its own blood supply
Which side of the hearts ventricle is thicker and why
Left ventricle is thicker as it contains oxygenated blood and it also needs to contract with more power as it is supplying blood to the whole body
