Statement Chordates have a tail extending posterior to the anus. It contains skeletal elements and muscles but lacks coelom and visceral organs.
Reason In aquatic organisms, it acts as a balancing organ.
Important Questions on Phylum Chordata
Which of the key adaptations helped evolutionary success of Reptiles on land?
A Warm-bloodedness
B. Pulmonary respiration and dry scaly skin
C. Internal fertilisation
D. Amniotic & Cleidoic eggs
Statement (S) : The amphibian blood is composed of erythrocytes, leucocytes and thrombocytes. The thrombocytes help in haemostasis.
Reason (R): The haemostasis regulates the body temperature in poikilotherms.
Which of the following is true?
Match the following
| List - I | List - II | ||
| (a) | Chelonia | (i) | Alligator |
| (b) | Rhynchocephalia | (ii) | Chameleon |
| (c) | Crocodilia | (iii) | Sphenodon |
| (d) | Squamata | (iv) | Testudo |
The correct answer is
Match the following
| List - I | List - II | ||
| (a) | Each half of the lower jaw is formed by 6 bones | (i) | Aves |
| (b) | Lacrimal and Harderian glands appeared for the first time | (ii) | Reptiles |
| (c) | Presence of only right systemic arch | (iii) | Amphibians |
| (d) | Each half of the lower jaw is made of single bone | (iv) | Mammals |
Study the following and pick up the correct combinations.
| S.No | Class | Unique character | Flourished in |
| I) | Amphibia |
Buccopharyngeal respiration |
Carbonferous period |
| II) | Reptilia | Jacobson organs | Mesozoic era |
| III) | Mammalia | Pinna | Coenozoic era |
| IV) | Pisces | Meninx primitiva | Cretaceous period |
| Zoological name | Common name | ||
| A | Ornithorhyncus | I | Flying fox |
| B | Pteropus | II | Kangaroo |
| C | Panthera | III | Blue whale |
| D | Macropus | IV | Tiger |
| V | Duck billed platypus |
The correct match is
Assertion (A): During pulmonary respiration in frog, buccopharyngeal cavity acts like a force pump.
Reason (R): When the floor of buccopharyigeal cavity is lowered, air forces the glottis to open and reach the lungs.
The correct option among the following is:
