You can find NCERT Solutions Class 11 Biology Chapter 4 on ALLEN. They provide clear answers to NCERT textbook questions and help students revise Animal Kingdom.
NCERT Solutions Class 11 Biology Chapter 4 cover animal classification, levels of organisation, symmetry, germ layers, coelom, non-chordates, Chordata, and major vertebrate groups.
NCERT Solutions Class 11 Biology Chapter 4 explain that animal classification helps group animals based on features such as body organisation, symmetry, germ layers, coelom, segmentation, and notochord.
NCERT Solutions Class 11 Biology Chapter 4 explain that diploblastic animals have two germ layers, while triploblastic animals have three germ layers.
NCERT Solutions Class 11 Biology Chapter 4 cover Porifera, Coelenterata, Ctenophora, Platyhelminthes, Aschelminthes, Annelida, Arthropoda, Mollusca, Echinodermata, Hemichordata, and Chordata.
NCERT Solutions Class 11 Biology Chapter 4 explain that Chordates are identified by features such as the notochord, dorsal hollow nerve cord, and paired pharyngeal gill slits.
NCERT Solutions Class 11 Biology Chapter 4 help students revise the distinguishing characteristics of Chondrichthyes and Osteichthyes and understand their position in vertebrate classification.
Yes, NCERT Solutions Class 11 Biology Chapter 4 help students revise important NCERT concepts related to animal classification, phyla, Chordata, and vertebrate groups. These concepts are useful for CBSE board exams and provide a strong foundation for NEET preparation.
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NCERT Solutions Class 11 Biology Chapter 4 - Animal Kingdom
NCERT Solutions for Class 11 Biology Chapter 4, Animal Kingdom, explain the diversity and classification of animals based on their structural and developmental features. The chapter covers important concepts such as levels of organisation, body symmetry, germ layers, coelom, segmentation, and notochord.
NCERT Solutions for Class 11 Biology Chapter 4 by ALLEN explain the identifying features of major animal groups, including Porifera, Ctenophora, Annelida, Arthropoda, Mollusca, Echinodermata, and Chordata. Students can learn about important features such as the water vascular system in Echinodermata and the notochord in Chordata, along with the characteristics of Cyclostomata, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia. These solutions follow the concepts covered in NCERT Class 11 Biology Chapter 4 and make animal classification easier to understand.
Class 11 Biology Chapter 4, Animal Kingdom, explains the basis of animal classification and the important characteristics of different animal groups. The key concepts covered in this chapter include:
Basis of Classification: Understand the main features used to classify animals, including levels of organisation, symmetry, germ layers, coelom, segmentation, and notochord.
Levels of Organisation: Study the cellular, tissue, organ, and organ system levels of organisation found in different animal groups.
Symmetry: Understand radial and bilateral symmetry and how they differ in animal body organisation.
Germ Layers: Learn the difference between diploblastic and triploblastic animals based on the number of germ layers present during development.
Coelom: Understand the classification of animals as acoelomates, pseudocoelomates, and coelomates based on the presence and nature of the body cavity.
Non-Chordates: Study the important features and examples of Porifera, Coelenterata, Ctenophora, Platyhelminthes, Aschelminthes, Annelida, Arthropoda, Mollusca, Echinodermata, and Hemichordata.
Phylum Chordata: Learn the main chordate characteristics, including the notochord, dorsal hollow nerve cord, and paired pharyngeal gill slits.
Classification of Vertebrata: Study the major vertebrate groups, including Cyclostomata, Chondrichthyes, Osteichthyes, Amphibia, Reptilia, Aves, and Mammalia, along with their important characteristics.
What are the difficulties that you would face in classification of animals, if common fundamental features are not taken into account?
Ans. The common fundamental features used for classifying animals include arrangement of cells, nature of coelom, level of organisation, symmetry of body, patterns of digestive, circulatory and reproductive systems. If these fundamental features are not taken into account, animal classification would become very confusing and difficult.
If you are given a specimen, what are the steps that you would follow to classify it?
Ans. Various steps considered to classify a specimen are:
Level of organisation : Cellular, tissue, organ or organ-system level.
Body symmetry : Asmmetrical, radical or bilateral symmetry.
Germ layers : Diploblastic of triploblastic.
Body cavity (coelom) : Acoelomate, pseudocoelomate or coelomate.
Segmentation : Presence or absence of segmentation.
Presence or absence of notochord : Used particularly for distinguishing chordates from non-chordates.
How useful is the study of the nature of body cavity and coelom in the classification of animals?
Ans. Organisms can be classified according to presence or absence of the coelom. The body cavity, which is lined by mesoderm is called coelom. Animals possessing coelom are called coelomates, e.g., annelids, molluscs, arthropods, echinoderms, hemichordates and chordates. In some animals, the body cavity is not lined by mesoderm, instead, the mesoderm is present as scattered pouches in between the ectoderm and endoderm. Such a body cavity iscalled pseudocoelom and the animals possessing them are called pseudocoelomates, e.g., aschelminthes. In pseudocoelomates, body cavity is derived from blastocoel of the embryo. The animals in which the body cavity is absent are called acoelomates, e.g., platyhelminthes.
Distinguish between intracellular and extracellular digestion.
Ans. Differences between intracellular and extracellular digestion are:
Intracellular digestion
Extracellular digestion
It occurs inside the cell.
It occurs outside the cell in the cavity of the alimentary canal.
Digestive enzymes are secreted by surrounding cytoplasm into the food vacuoles.
Digestive enzymes secreted by special cells into the cavity of alimentary canal by ducts.
The products of digestion diffuse into the cytoplasm.
The products of digestion are absorbed the intestinal wall.
5. What is the difference between direct and indirect development?
Ans. Differences between direct development and indirect development are :
Direct development
Indirect development
Young ones may resemble the adult.
In this young hatchlings (larvae) do not resemble the adult.
Intermediate stages are absent.
Intermediate stages are present.
Metamorphosis is absent.
Metamorphosis is seen in indirect development.
E.g., Hydra, man
E.g., Frog, cockroach
6. What are the peculiar features that you find in parasitic platyhelminthes?
Ans. Following are the peculiar features of parasitic platyhelminthes:
(i) The thick tegument (body covering) resistant to the host's digestive enzymes and antitoxins.
(ii) Adhesive organs like suckers in flukes and the hooks and suckers in tapeworms provide a firm grip on or in the host's body.
(iii) Loss of locomotory organs.
(iv) Digestive organs are absent in tapeworms because digested and semidigested food of the host is directly absorbed' through the body surface.
7. What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?
Ans. Arthropods are most successful animals and constitute the largest group of the animal kingdom because :
The have conquered land, sea and air and occupy a wide range of habitats. They have a thick, tough and non-living chitinous cuticle, which forms an exoskeleton and protects them from predators.
The exoskeleton also provides support and prevents water loss, helping them survive on land. They possess jointed appendages, which are modified for different functions such as walking, swimming, feeding and sensing.
They have well-develolped organ systems and highly specialised body structures.
Hence, their adaptability, protective exoskeleton and specialised appendages make arthropoda the largest and most successful animal phylum.
Water vascular system is the characteristic of which group among the following ?
"All vertebrates are chordates but all chordates are not vertebrates". Justify the statement.
Ans. Chordates are the animals that possess notochord (a stiff, supporting rod like structure present on the dorsal side) at some stage of their lives. Phylum Chordata is divided into three Subphyla: Urochordata or tunicata, Cephalochordata and Vertebrata. Subphyla Urochordata and Cephalochordata are often referred to as protochordates and are exclusively marine. In urochordata, notochord is present only in tail of larva and disappears in adults, while in cephalochordata, it extends from head to tail region and persists throughout the life.
The members of Subphylum Vertebrata a possess notochord during the embryonic period and is replaced by a cartilaginous or bony vertebral column in the adult. Thus all vertebrates are chordates but all chordates are not vertebrates.
How important is the presence of air bladder in Pisces?
Ans. Bony fishes have a sac-like outgrowth, the swim bladder also called air bladder, which arises from the dorsal wall of oesophagus. It is hydrostatic in function. It regulates buoyancy and helps them to swim up and down, thus preventing them from sinking. In some species air bladder also helps in respiration. It also serves as resonating chamber to produce or receive sound.
What are the modifications that are observed in birds that help them fly?
Ans. Birds have adapted to aerial mode of life through the following modifications:
(i) Body is streamlined and spindle shaped which minimise resistance to the wind.
(ii) Body is covered with feathers. It reduces the friction, prevent loss of heat and help to maintain constant temperature.
(iii) Forelimbs are modified into wings, which help during flight.
(iv) Flight muscles are greatly developed
(v) Most of the bones are pneumatic, hollow and filled with air which makes the body lighter and helps in flight.
Could the number of eggs or young ones produced by an oviparous and viviparous mother be equal? Why?
Ans. No, the number of eggs or young ones produced by an oviparous and viviparous mother respectively cannot be equal. Oviparous mother lays large number of eggs, as the eggs are laid outside the body, so they are not protected from predators and harsh environmental conditions, and therefore destroyed. However in viviparous mother, eggs are not laid outside, but the embryos develop inside the mother and thus are protected from the outside harsh environment, thus, the number of eggs produced are less. Therefore, the number of eggs or young ones produced by an oviparous and viviparous mother respectively cannot be equal.
Segmentation in the body is first observed in which of the following?
(a) Platyhelminthes
(b) Aschelminthes
(c) Annelida
(d) Arthropoda
Ans. (c) Annelida
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) Hair (vi) Cyclostomata and Chondrichthyes
(g) Choanocytes (vii) Mammalia
(h) Gill slits (viii) Osteichthyes
Prepare a list of some animals that are found parasitic on human beings.
Ans. List of some animals that are found parasitic on human beings :
Parasite
Direct development
Indirect development
Taenia solium (Pork Tapeworm)
Endoparasites
Small intestine
Schistosoma (Blood fluke)
Endoparasites
Hepatic portal system and mesenteric blood vessels.
Ancylostoma duodenale (Hook worm)
Endoparasites
Small intestine
Wuchereria (Filarial worm)
Endoparasites
Lymph nodes and lymphatic vessels.
Enterobius (Pin worm)
Endoparasites
Colon, caecum or vermiform appendix
3.0NCERT Class 11 Biology – Chapter-Wise Solutions & Explanations
Get chapter-wise NCERT Solutions for Class 11 Biology with thorough explanations of each question from the textbook. Learn key ideas, go over important chapters, and gain a firm foundation in Biology for your examinations.
4.0Key Features of NCERT Solutions for Class 11 Biology Chapter 4
Basis of Animal Classification: Understand the differences between diploblastic and triploblastic organisation, radial and bilateral symmetry, and acoelomate, pseudocoelomate, and coelomate body plans.
Distinctive Characteristics: Learn the identifying features of different animal groups, such as comb plates in Ctenophora, radula in Mollusca, and the water vascular system in Echinodermata.
Comparison of Animal Groups: Understand the important differences between Chondrichthyes and Osteichthyes and between Chordates and Non-Chordates.
Phyla and Classes: Learn about the classification of creatures into different phyla and classes based on their structural, anatomical and developmental properties.
Examples and Scientific Names: Study important examples and scientific names of animals from different phyla and classes to understand their classification more clearly.
NCERT-Based Explanations: Get clear and accurate explanations based on the concepts and terminology given in the NCERT Class 11 Biology syllabus.