Question

No of gill slits in Petromyzon are
(A) Seven pair
(B) ten pair
(C) Three pair
(D) None​

Answer 1

Answer:

(A) Seven pair

There are two dorsal finfolds, and there are seven open gill slits on each side.

Answer 2

Answer:

The right answer is (A) Seven pair.

Explanation:

• Seven pairs of gill slits are present in Petromyzon.
• Petromyzon are mostly found in fresh and salt-water.
• It belongs to the phylum Chordata.
• Petromyzon have a dorsal tubular nerve cord, notochord and gill-slits  and have a definite head.
• They have a cranium with simple brain, jaws and appendages are absent in them.
• It has 7 gill pairs, which are open independently to exterior and the branchial basket is well developed.
• The function of these slits is used to filter food particles from the water.

• Therefore, the right answer is (A) Seven pair.