,Circulation is the transport of nutrients, oxygen, CO2 and excretory products to the concerned
tissues or organs.
For circulation, simple organisms (sponges, coelenterates etc) use water from their
surroundings.
Complex organisms use body fluids (blood & lymph) for circulation.
Here, the blood pumped by the heart passes through large vessels into open spaces or cavities
called sinuses.
E.g. Arthropods and molluscs.
Here, blood pumped by the heart is circulated through blood vessels.
It is more advantageous as the flow of fluid can be precisely regulated.
E.g. Annelids and chordates.
, It is seen in fishes.
Heart receives impure blood only (venous
heart).
Deoxygenated blood from heart →
oxygenated by gills → supplied to body
parts → deoxygenated blood → to heart.
It is seen amphibians & reptiles.
Left atrium receives oxygenated blood from
gills/lungs/skin. Right atrium gets
deoxygenated blood from other body parts.
However, they get mixed up in the single
ventricle.
Ventricle pumps out mixed blood.
tissues or organs.
For circulation, simple organisms (sponges, coelenterates etc) use water from their
surroundings.
Complex organisms use body fluids (blood & lymph) for circulation.
Here, the blood pumped by the heart passes through large vessels into open spaces or cavities
called sinuses.
E.g. Arthropods and molluscs.
Here, blood pumped by the heart is circulated through blood vessels.
It is more advantageous as the flow of fluid can be precisely regulated.
E.g. Annelids and chordates.
, It is seen in fishes.
Heart receives impure blood only (venous
heart).
Deoxygenated blood from heart →
oxygenated by gills → supplied to body
parts → deoxygenated blood → to heart.
It is seen amphibians & reptiles.
Left atrium receives oxygenated blood from
gills/lungs/skin. Right atrium gets
deoxygenated blood from other body parts.
However, they get mixed up in the single
ventricle.
Ventricle pumps out mixed blood.
