Classification of Animals Test - 8

A) Tube feet help in respiration in echinoderms.

B) Aristotle's lantern is a dental apparatus which is used in mastication/chewing/scraping food off rocks.

C) In echinoderms, excretion is carried out through diffusion from the body tissues to the coelomic fluid from where the excreta is eliminated through the anus.

D) The endoskeleton of echinoderms which is made of calcareous ossicles provides support.

So the answer is 'Mastication'.

Scales are the primary feature of the fishes but not all fish have them. Some fishes are scaleless such as Cat-fish, torpedo etc. Hence, option C is correct.

In vertebrates, the notochord is replaced by the vertebral column during embryonic development (in mammals, it is retained only as a small gel-like core in each intervertebral disc ). Early vertebrates usually had a large notochord as well as a vertebral column.

So, the correct option is, 'notochord; a vertebral column'.

Tube feet are the many small tubular projections found on the oral surface of a sea vascular system of the echinoderm phylum. The main function of the tube is to provide locomotion, respiration, and feeding. In the arms of starfishes, they are arranged in grooves and operated by hydraulic pressure.
Therefore, the correct answer is option D.

Small (baby) fishes are called as fry or hatchling. They are the young animal that recently hatched out from the egg. They have included in superclass Pisces.

 Hence, option C is correct.

The animals who posses a proper notochord are known as vertebrates whereas the organisms who do not have a proper notochord are known as invertebrates.

 Hence, option A is correct.

Craniata, include all animals having a skull/cranium, be it cartilaginous or bony. It includes vertebrates. Euchordata has a skeleton and a skull to protect the brain. It includes vertebrates. Hence, option D is correct.

Fishes have two chambered heart i.e., one auricle and one ventricle. There is mixing of pure and impure blood and hence they are cold blooded. Amphibians and reptiles (except crocodile) have three chambered heart. Crocodiles, birds and mammals have a four-chambered heart. Thus, the correct answer is option B.

Vertebrata is sub-phyla of phylum Chordata. Animals of phylum Chordata are characterised by presence of notochord.

 Hence, option A is correct.

All the fishes live in water all of the time and inhale dissolved oxygen through gills. They have special structures called as fins, which help them to move through the water. The body of a fish is long and thin and pointed at both ends. This is called as a streamlined shape. Apart from fishes some amphibians like frog, reptiles like crocodile and birds like duck can survive in water.

 Hence, option B is correct.

Pterichthys is a genus of Devonian fossil fishes with winglike appendages.
Coccostei or seed bone is an extinct genus of arthrodire placoderm (pre-historic fishes).
Acanthodii is a paraphyletic class of extinct fishes, sharing features with both bony and cartilaginous fishes. Thus, the correct answer is option D.

The vertebral column is a supportive structure derived from the notochord. It is more commonly called the backbone or the spine. Animals that do not possess or develop a vertebral column or backbone are commonly called invertebrates. They include crabs, snails, lobsters, octopuses, sea urchins, worms, etc.

So, the correct answer is 'Invertebrates'.

Non-chordates are characterized by a central nervous system that is ventral, solid and double. There is no notochord present and a post-anal tail is also absent. Heart, if present is dorsal. 

So, 'ventrally located heart' is not the feature of non-chordates and hence it is the right answer.

A. Dermal scales are the projections from the dermis of an animal.

B. Epidermal scales are the extension of epidermal layer into projections.

C. Lateral line organs is a system of sense organs (for the perception of vibration, movement or pressure in the surrounding water) present in aquatic vertebrates such as fishes.

Fishes have dermal scales such as placoid scales and have lateral line sense organs. 

Hence, both options A and C are correct. So, the correct answer is 'Both A and C'.

Non chordates are generally poorly developed. The blood is generally colorless in all nonchordates. The flow of blood is backward in ventral blood vessels and forward in a dorsal blood vessel.

 Hence, option B is correct.