In which of these examples are the members exclusively chondrichthyes
1. | Scoliodon, Pristis, Labeo, Betta |
2. | Scoliodon, Pristis, Betta, Trygon |
3. | Scoliodon, Trygon, Pristis, Carcharodon |
4. | Scoliodon, labeo, Carcharodon, Pristis |
Which of the following statement/s about chondrichthyes are incorrect?
1) | Notochord is persistent throughout life |
2) | Endoskeleton is made up of bones |
3) | Operculum present |
4) | Skin is covered by placoid scales |
1. | All of the above |
2. | None of the above |
3. | 1 and 4 are incorrect |
4. | 2 and 3 are incorrect |
In males pelvic fins bear claspers in
1. Carcharodon
2. Pterophyllum
3. Exocoetus
4. Labeo
Which of the following characteristic features always holds true for the corresponding group of animals?
1. | Viviparous | Mammalia |
2. | Possess a mouth with an upper and a lower jaw | Chordata |
3. | 3-chambered heart with one incompletely divided ventricle | Reptilia |
4. | Cartilaginous – endoskeleton | Chondrichthyes |
A marine cartilaginous fish that can produce electric current is
(1) Pristis
(2) Torpedo
(3) Trygon
(4) Scoliodon
Select the correct option in respect of characteristics
of each group :-
Cyclostomes |
Chondrichthyes |
Osteichthyes |
|
(i) |
Marine |
Marine, Fresh water |
Marine |
(ii) |
Sucking mouth |
Ventral mouth |
Terminal mouth |
(iii) |
6-15 Pairs of Gills |
5-7 Pairs of Gills |
4 Pairs of Gills |
(iv) |
Placoid scales |
Cycloid Scales |
Ctenoid/ Ganoid |
1. | (i), (ii) are correct. |
2. | (i), (iii), (iv) are correct. |
3. | (ii), (iii) are correct. |
4. | (ii), (iii), (iv) are correct. |
Read the following statements :
A. | Mouth is located ventrally. |
B. | Notochord is persistent throughout life. |
C. | Gill slits are seperate and with operculum. |
D. | Air bladder are absent. |
How many of the above statements are correct for given
figure :
1. Four.
2. Three.
3. Two.
4. One