circulatory system of cockroach differs from that of the earth worm in:
1) lacking capillary network
2) lacking large blood vessels
3) possessing valves in large blood vessels
4) having a higher speed of circulation
In cockroaches the circulatory system is open and hence no capillaries and veins are present in them. Thus, the correct answer ot this question will be lacking a capillary network.
In earthworm the circulatory system is open i.e. the blood flows in the blood vessels.
Hope, the answer is clear to you.
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