Question

Which of the following is NOT characteristic of phylum Cnidaria? Epitheliomuscular cells Nerve net Open circulatory system Gastrovascular cavity Mesoglea

Answer 1

ANS 1 ) The correct answer for this question is -

c) Open circulatory system

Explanation -

Cnidaria also called coelentrate have mesoglea, gastrovascular cavity, nerve net and epitheliomuscular cell but it not contain any circulatory system .

hence it not contain open or closed circulatory system.

Hence the correct option is - c)

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Ans 2) The correct answer for this question is -

d) gastropoda

Explanation -

The rotation of shell and visceral mass with 180 degree angle is called torsion . Torsion is the characteristic feature of gastropods .

Hence correct answer is option - d)

Ans 3) The correct answer for this question is -

a) Metamerism

Explanation -

Metameric segmentation is the segmented body devided in to metamer . And this type of segmentation found in annelida and arthopoda bot not in nematoda .

hence option - a) is correct answer.

Ans 4) The correct answer for this question is -

a) closed circulatory system

Explanation -

Mollusca is soft bodied organism . Usually mollusca have open circulatory system but in cephalopoda closed circulatory system found .

Hence The correct option is - a) closed circulatory system

Ans 5) The correct answer for this question is -

a) Insecta

Explanation -

Insecta is the arthopods. The circulatory system of arthopoda is different . It contain hemolymph in their fluid which not able to carry oxygen . It not contain hemoglobin . Hence their circulatory system not able to deliver oxygen to body cell .it deliver oxygen by tracheal system.

hence the correct option is -a) insecta