In: Biology
Spiders have what kind of circulation?
A. Closed circulation with blood vessels
B. Intermediate circulation with some vessels and some areas where the fluid moves directly around tissues
C. Open circulation with fluid bathing all organs and tissues
D. None of the above
Answer :- "C" i.e Open circulation with fluid bathing all organs and tissues.
Explanation :- We know the majority of multicellular animals have developed a circulatory system for mass transport of nutrients and respiratory gases and blood.
Blood circulatory system is basically of two types : open and closed. Closed blood vascular system occurs in annelids , some molluscs and vertebrates in which blood is circulated in the blood vessels. Arthropods and most molluscs have an open type of circulatory system in which the blood flows in spaces , the sinuses. We know spider is a arthropods so it have open circulatory system. In spider blood colour is pale bluish due to the presence of respiratory pigment , haemocyanin.
In open circulatory system blood is not closed in the blood vessels rather it pumped through a cavity called hemocoel and pumped back to heart so tissues and organs are surround or bathed by blood.
So from the above discussion we can conclude that the answer is option C.