NCTB Class 8 science Chapter 1 “Classification of Animal World” Solution
Bangladesh Board Class 8 science Solution Chapter 1 “Classification of Animal World” Exercises Question and Answer by Experienced Teacher.
NCTB Solution Class 8 Chapter 1 “Classification of Animal World”
|NCTB Bangladesh Board|
“Classification of Animal World”
Fill in the blanks:-
(1) Answer:- Flame cell.
(3) Answer:- Molluscs.
(4) Answer:- Vertebrate.
(5) Answer:- Notochord.
Short answered question:-
(1) Answer:- There are 2 part in binomial nomenclature of an animal.
The name of these parts are genus and species.
The scientific name of human is Homo sapiens.
(2) Answer:- The names of five known arthropods are prawn, butterfly, cockroach, crab, crab.
(3) Answer:- Prawn belongs to arthropods phylum. The characteristics of this phylum are —
(a) Body is segmented and joint appendages are present.
(b) Head bears a pair of compound eyes and antenna.
(c) Soft body is covered with hard chitin us exoskeleton.
(d) Body cavity field with blood and is known as haemocoel.
(4) Answer:- The characteristics of mammals:-
(a) Body covered with hair.
(b) Female mammal suckle their young on milk from mammary glands.
(c) Warm blooded animal.
(d) Four chambered heart.
(e) Teeth heterodont.
(f) All the mammal give birth to child.
(5) Answer:- The characteristics of urochordate:
(a) Notochord present only in larval stage and restricted to the tail
(b) Gill slits and dorsal tubular never cord present only in the early stage of the life cycle.
Multiple choice questions:-
(1) Answer:- (d) Mussel.
(2) Answer:- (c) (ii) & (iii).
(3) Answer:- (a) M.
(4) Answer:- (a) (i).
(1) (a) Answer:- Classification is an easy way to know the structure and nature of such Hugh number of animals.
(1) (b) Answer:- Scientific name is a naming system which consists two parts genus and species and it must be in Latin or Latinized language or in English.
(1) (c) Answer:- ‘P’ belongs to class Arthropoda because it has same characteristics as Arthropoda, like body is segmented, head bears antenna, a pair of compound eyes etc.
(1) (d) Answer:- These two animals belong to different classes because their characteristics are different from each other. ‘P’ belongs to invertebrates and ‘Q’ belongs to vertebrate.
(2) (a) Answer:- tape worm belong to phylum Platyhelminthes.
(2) (b) Answer:- Notochord is present only in embryonic stage and replaced by vertebral column in adults of human.
(c) Answer:- Based on Rahat’s observation, the systematic position of the animal, it belongs to Arthropoda, it has antenna, compound eyes, its body is segmented, it has wings to fly, joint appendages are present.
(2) (d) Answer:- It is important for Rahat to know the systematic position of the animal. If Rahat know the systematic position of the animal than he can identify group, name the animals.