NCERT Solutions for Class 11 Biology Chapter 4
Animal Kingdom Class 11
Chapter 4 Animal Kingdom Exercise Solutions
Exercise : Solutions of Questions on Page Number : 62
Q1 :
What are the difficulties that you would face in classification of animals, if common fundamental features are not taken into account?
Answer :
For the classification of living organisms, common fundamental characteristics are considered.
If we consider specific characteristics, then each organism will be placed in a separate group and the entire objective of classification would not be achieved.
Q2 :
If you are given a specimen, what are the steps that you would follow to classify it?
Answer :
Q3 :
How useful is the study of the nature of body cavity and coelom in the classification of animals?
Answer :
Q4 :
Distinguish between intracellular and extracellular digestion?
Answer :
Intracellular digestion |
Extracellular digestion |
||
1. |
The digestion of food occurs within the cell. |
1. |
The digestion occurs in the cavity of alimentary canal. |
2. |
Digestive enzymes are secreted by the surrounding cytoplasm into the food vacuole. |
2. |
Digestive enzymes are secreted by special cells into the cavity of alimentary canal. |
3. |
Digestive products are diffused into the cytoplasm. |
3. |
Digestive products diffuse across the intestinal wall into various parts of the body. |
4. |
It is a less efficient method. |
4. |
It is a more efficient method of digestion. |
5. |
It occurs in unicellular organisms. |
5. |
It occurs in multicellular organisms. |
|
|
|
|
||
Q5 :
What is the difference between direct and indirect development?
Answer :
|
Direct development |
|
Indirect development |
|
1. |
It is a type of development in which an embryo develops into a mature individual without involving a larval stage. |
1. |
It is a type of development that involves a sexually-immature larval stage, having different food requirements than adults. |
|
2. |
Metamorphosis is absent. |
2. |
Metamorphosis involving development of larva to a sexually-mature adult is present. |
|
3. |
It occurs in fishes, reptiles, birds, and mammals. |
3. |
It occurs in most of the invertebrates and amphibians. |
|
|
|
|||
Q6 :
What are the peculiar features that you find in parasitic platyhelminthes?
Answer :
Taenia (Tapeworm) and Fasciola (liver fluke) are examples of parasitic platyhelminthes. Peculiar features in parasitic platyhelminthes are as follows.
1. They have dorsiventrally flattened body and bear hooks and suckers to get attached inside the body of the host.
2. Their body is covered with thick tegument, which protects them from the action of digestive juices of the host.
3.
Q7 :
What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?
Answer :
The phylum, Arthropoda, consists of more than two-thirds of the animal species on earth. The reasons for the success of arthropods are as follows.
i. Jointed legs that allow more mobility on land
ii. Hard exoskeleton made of chitin that protects the body
iii.
Q8 :
Water vascular system is the characteristic of which group of the following:
(a) Porifera (b) Ctenophora (c) Echinodermata (d) Chordata
Answer :
Q9 :
"All vertebrates are chordates but all chordates are not vertebrates". Justify the statement.
Answer :
Q10 :
How important is the presence of air bladder in Pisces?
Answer :
Q11 :
What are the modifications that are observed in birds that help them fly?
Answer :
Birds have undergone many structural adaptations to suit their aerial life. Some of these adaptations are as follows.
(i) Streamlined body for rapid and smooth movement
(ii) Covering of feathers for insulation
(iii) Forelimbs modified into wings and hind limbs used for walking, perching, and swimming
(iv) Presence of pneumatic bones to reduce weight
(v)
Q12 :
Could the number of eggs or young ones produced by an oviparous and viviparous mother be equal? Why?
Answer :
The numbers of eggs produced by an oviparous mother will be more than the young ones produced by a viviparous mother. This is because in oviparous animals, the development of young ones takes place outside the mother's body. Their eggs are more prone to environmental conditions and predators. Therefore, to overcome the loss, more eggs are produced by mothers so that even under harsh environmental conditions, some eggs might be able to survive and produce young ones. On the other hand, in viviparous organisms, the development of young ones takes place in safe conditions inside the body of the mother. They are less exposed to environmental conditions and predators.
Q13 :
Segmentation in the body is first observed in which of the following:
(a) Platyhelminthes (b) Aschelminthes (c) Annelida (d) Arthropoda
Answer :
Q14 :
Match the following:
(a) Operculum |
(i) Ctenophora |
(b) Parapodia |
(ii) Mollusca |
(c) Scales |
(iii) Porifera |
(d) Comb plates |
(iv) Reptilia |
(e) Radula |
(v) Annelida |
(f) Hairs |
(vi) Cyclostomata and Chondrichthyes |
(g) Choanocytes |
(vii) Mammalia |
(h) Gill slits |
(viii) Osteichthyes |
Answer :
|
Column I |
|
Column II |
|
(a) |
Operculum |
(viii) |
Osteichthyes |
|
(b) |
Parapodia |
(v) |
Annelida |
|
(c) |
Scales |
(iv) |
Reptilia |
|
(d) |
Comb plates |
(i) |
Ctenophora |
|
(e) |
Radula |
(ii) |
Mollusca |
|
(f) |
Hairs |
(vii) |
Mammalia |
|
(g) |
Choanocytes |
(iii) |
Porifera |
|
(h) |
Gill slits |
(vi) |
Cyclostomata and Chondrichthyes |
|
|
|
|||
Q15 :
Prepare a list of some animals that are found parasitic on human beings.
Answer :
S. No. |
Name of organism |
Phylum |
1 |
Taenia solium |
Platyhelminthes |
2 |
Fasciola hepatica |
Platyhelminthes |
3 |
Ascaris lumbricoides |
Aschelminthes |
4 |
Wuchereria bancrofti |
Aschelminthes |
5 |
Ancyclostoma |
Aschelminthes |