Q. Read the given statements about the blood vascular system of cockroach.
I. The circulatory system of cockroach is of closed type
II. It contains no blood vessels except aorta of the heart.
III. The heart is 6-chambered.
IV. The haemolymph is composed of colourless plasma and haemocytes.
Which of the statement(s) given above is/are INCORRECT?

 2758  198 NTA AbhyasNTA Abhyas 2020Structural Organisation in Animals Report Error

Solution:

Cockroaches belong to Phylum Arthropods. These show open type of circulation as proper system of blood vessels and heart is not seen. Circulation is through open sinuses. Only one blood vessel is seen i.e. Aorta in the head region. Heart in cockroaches are on the dorsal side and consists of 13 chambers. The circulatory fluid is haemolymph that consists of colourless plasma and haemocytes.