Question: 171 Select the correct statements with reference to chordates.
A. Presence of a mid-dorsal, solid and double nerve cord.
B. Presence of closed circulatory system.
C. Presence of paired pharyngeal gillslits.
D. Presence of dorsal heart
E. Triploblastic pseudocoelomate animals.
Choose the correct answer from the options given below:
(1) B, D and E only
(2) C, D and E only
(3) A, C and D only
(4) B and C only
Answer: Option (4)
Explanation:
In chordates, the nerve cord is dorsal, hollow and single, not mid-dorsal, solid and double,
so statement A is incorrect.
Chordates possess a closed circulatory system, so statement B is correct.
Paired pharyngeal gill slits are a characteristic feature of chordates,
present at least during some stage of their life cycle, so statement C is correct.
Chordates have a ventral heart, not a dorsal heart, so statement D is incorrect.
Chordates are triploblastic coelomate animals, not pseudocoelomate, so statement E is incorrect.
Therefore, the correct statements are B and C.