The structure present in all adult vertebrates is
Notochord
Dorsal tubular nerve cord
Pharyngeal gill slits
All of these
B.
Dorsal tubular nerve cord
Dorsal tubular nerve cord is the characteristic feature of all adult vertebrate. It is a gel-like substance and is remnant of the notochord.
A horse and a donkey can breed to produce mule which is an infertile animal. The infertility is because horse and donkey belong to different.
Class
Order
Species
Genus
Match the following Columns.
| Column I (organism) | Column II (Connecting Link) |
| A. Echina | 1. Between Annelida and Mollusca |
| B. Peripatus | 2. Between Reptiles and Mammals |
| C. Neopilina | 3. Between Annelida and Arthropoda |
| D. Protopterus | 4. Between Pisces and Amphibian |
A – 4; B – 3; C – 2; D – 1
A – 2; B – 3; C – 1; D – 4
A – 3; B – 1; C – 2; D – 4
A – 4; B – 2; C – 1; D – 3
Consider the following statements and Choose correct ones from given options.
(I) Shark do not have any bone in its body.
(II) Water snake and salamander belongs to same class and have largest RBC.
(III) Silver fish is a true fish while cuttle and star fishes are mollusks and echinoderms respectively.
(IV) Ornithorhynchus is a connecting link between reptiles and mammals.
I, II and IV
I and IV
I, II and III
III and IV
Animals of class-Mammalia have
Seven cervical vertebrae
Seven cranial nerve
Single ventricular chamber
Fourteen cervical vertebrae
Chondrichthyes is characterised by
Placoid scale
Ventral mouth
Ctenoid scale and ventral mouth
Placoid scale and ventral mouth
