Q3 of 525 Page 239

Why are whales not grouped in fishes?

Although both whales and fishes are aquatic, both belong to different classes. Whales belong to class Mammalia while fishes belong to class Pisces. Both differ in several basic characters, such as:

(i) Whales are warm-blooded animals while fishes are cold-blooded animals.


(ii) Whales have lungs for respiration while fishes have gills for respiration.


(iii) Whales have four-chambered heart while fishes have two-chambered heart.


(iv) Whales have mammary glands which are absent in fishes.


More from this chapter

All 525 →
1

Wins are absent in bed bug even then it is considered an insect. Why?

 2

Why are protozoa are regarded as early animals?

 1


(a) Identify figures A to F?


(b) What is the phylum of D, E and F?


(c) What is the division of A, B, and C?


(d) Which of them is unicellular and eularyotic organism?


(e) Which one of them exhibits (i) Heterotrophic nutrition; (ii) Micotrophic nutririon.


(f) Which one of them is multicellular decomposer?


(g) Which one amphibian of plant kingdom?


(h) In which one of them play xylem lacks vessels and phloem is without companion cells?


(i) What is the scientific name of esch of them: (i) Male shield fern; (ii) Bread mould?


(j) In which of them endosperm is haploid?

 2


(a) Identify figure A to D.


(b) Which one of them is (i) diplobalstic; (ii) Coelomate?


(c) Which triplobalstic animal is (i) Acoelomate; (ii) Coelomate?


(d) Which one belong to phylum


(i) Cnidaria; (ii) Platyhelminthes; (iii) Annelids; (iv) Arthropoda?


(e) Which one of them has


(i) Organ level organization?


(ii) Organ system level organization?


(f) Which one of them has excretory organs in the form of (i) Flame cells; (ii) Nephridia?


(g) Which one of them has trachea as the respiratory organ?