MCQ
Read the following statements.
(A) Fertilisation is external with direct development in echinoderms.
(B) Echinus is commonly known as sea urchin; Antedon as sea lily; and Cucumaria as sea cucumber.
(C) Asterias is commonly called star fish and ophiura as brittle star.
(D) The body of hemichordate is cylindrical and composed of anterior proboscis, a collar and a long trunk.
(E) In hemichordate respiration takes place through gills and excretory organ is proboscis gland.
(F) Fertilisation is external with direct development in hemichordates.
(G) Chordates are fundamentally characterized by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits.
(H) Subphyla urochordata and cephalochordata are often referred to as protochordates and is exclusive marine.
(T) In urochordata, notochord is present only in adult tail.
(J) The notochord is replaced by a cartilaginous or bony vertebral column in the adult of vertebrata
(K) Cyclostomates are ectoparasites on some fishes. They have an elongated body bearing 6 - 15 pairs of gill slits for respiration.
(L) Chondrichthyes have sucking and circular mouth without Jaws. Their body is devoid of scales and paired fins.
(M) Cranium and vertebral column are cartilaginous in cyclostomes. After spawning, within few days they die.
(N) The mouth of cyclostomates is located ventrally and teeth are modified placoid scales which are backwardly directed.
(0) Due to the absence of air bladder chondrichthyes have to swim constantly to avoid sinking.
(P) Gill cover is known as operculum, which are absent in chondrichthyes.
(Q) In some species of chondrichthyes like torpedo have poison string and trygon have electric organ.
Choose the correct option given below :-
(A) Fertilisation is external with direct development in echinoderms.
(B) Echinus is commonly known as sea urchin; Antedon as sea lily; and Cucumaria as sea cucumber.
(C) Asterias is commonly called star fish and ophiura as brittle star.
(D) The body of hemichordate is cylindrical and composed of anterior proboscis, a collar and a long trunk.
(E) In hemichordate respiration takes place through gills and excretory organ is proboscis gland.
(F) Fertilisation is external with direct development in hemichordates.
(G) Chordates are fundamentally characterized by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits.
(H) Subphyla urochordata and cephalochordata are often referred to as protochordates and is exclusive marine.
(T) In urochordata, notochord is present only in adult tail.
(J) The notochord is replaced by a cartilaginous or bony vertebral column in the adult of vertebrata
(K) Cyclostomates are ectoparasites on some fishes. They have an elongated body bearing 6 - 15 pairs of gill slits for respiration.
(L) Chondrichthyes have sucking and circular mouth without Jaws. Their body is devoid of scales and paired fins.
(M) Cranium and vertebral column are cartilaginous in cyclostomes. After spawning, within few days they die.
(N) The mouth of cyclostomates is located ventrally and teeth are modified placoid scales which are backwardly directed.
(0) Due to the absence of air bladder chondrichthyes have to swim constantly to avoid sinking.
(P) Gill cover is known as operculum, which are absent in chondrichthyes.
(Q) In some species of chondrichthyes like torpedo have poison string and trygon have electric organ.
Choose the correct option given below :-
- AB,C,D,E, K are correct
- BA, F, I, L, N, Q are incorrect
- CG, H, J, K, M, O Pare correct
- ✓All of the above