NCERT Solutions for Class 11 Biology Chapter 4 - Animal Kingdom

NCERT Solutions for Class 11 Biology Chapter 4 Animal Kingdom Download PDF

Students who need help with animal classification can read Chapter 4. It covers everything from sponges to mammals. Students can download the Animal Kingdom Class 11 questions and answers PDF from the link given below. Having ready-to-use solutions makes a big difference during preparation. The NCERT Solutions for Class 11 Biology are perfect for last-minute preparation or regular revision.

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Also Read,

• NCERT Notes for Class 11 Biology Animal Kingdom
• NCERT Exemplar for Class 11 Biology Animal Kingdom

Class 11 Biology Chapter 4 Animal Kingdom NCERT Question Answer

Given below are the detailed solutions to all the questions given in the textbook. All the answers are prepared by subject experts, following the latest NCERT curriculum. Students can refer to the Class 11 Biology Chapter 4 Animal Kingdom question answer for better understanding.

Q1. What are the difficulties that you would face in the classification of animals if common fundamental features are not taken into account?

Answer: Basic characteristics help group animals and indicate their differences. Animals lack cell walls and are heterotrophic; mammals and other groups have additional distinguishing features (e.g., mammary glands in mammals). Without common fundamental features:

• It would be difficult to determine relationships among animals.

• Classification would become confusing and inconsistent.

• Understanding evolutionary history would be much harder.

In brief, these basic characteristics form the basis of animal classification and help us understand evolution.

Q2. If you are given a specimen, what are the steps that you would follow to classify it?

Answer: To identify an unknown specimen, look at these most important features:

1. Level of Organisation: Cells, tissues, or organs.

2. Body Symmetry: Radial or bilateral.

3. Germ Layers: Two (diploblastic) or three (triploblastic).

4. Body Cavity: Present or absent.

5. Coelom: True (coelomate), false (pseudocoelomate), or none (acoelomate).

Q3. How useful is the study of the nature of the body cavity and coelom in the classification of animals?

Answer: The coelom and body cavities are important in the classification of animals. A coelom is a body cavity filled with fluid, lined by embryonic tissue.

• True coelomates are annelids, molluscs, arthropods, echinoderms, hemichordates, and chordates.
• Animals that lack a coelom (acoelomates) are Porifera, Coelenterata (Cnidaria), ctenophores, and platyhelminths.
• A pseudocoelom is present in some animals, which is not completely lined by mesoderm but develops from the blastocoel of the embryo. Aschelminthes fit into this category.

Dividing animals into categories according to their coelom helps us to understand their development and evolutionary history.

Q4. Distinguish between intracellular and extracellular digestion.

Answer: The differences between intracellular and extracellular digestion are as follows

Q5. What is the difference between direct and indirect development?

Answer: The differences between direct and indirect development are as follows

Q6. What are the peculiar features that you find in parasitic Platyhelminthes?

Answer: Platyhelminthes have several unique characteristics:

1. They have a thick tegument that shields them from the digestive enzymes of their hosts.

2. Their bodies are dorsoventrally flattened, i.e., flat from top to bottom.

3. They have suckers and hooks that help them stick to their hosts and obtain nutrition.

4. They lack well-developed locomotory organs; movement is by cilia and muscular action.

5. Their reproductive system is well developed, and they are mostly hermaphroditic, having both male and female reproductive organs.

Q7. What are the reasons that you can think of for the arthropods to constitute the largest group of the animal kingdom?

Answer: The reasons for arthropods being the largest group of animals are as follows:

1. They have a thick cuticle that helps them to thrive in many types of environments, particularly on land.

2. They have striated muscles that help in rapid and effective movement.

3. They have a tracheal system of respiration that brings oxygen directly to their cells, which is extremely effective.

4. They possess joint appendages that are capable of performing numerous different functions, so they are very adaptable.

5. They have a highly developed nervous system and sense organs that help them effectively sense and react to their surroundings.

6. They communicate using pheromones, which help in social behavior and reproduction.

Q8. The water vascular system is characteristic of which group of the following:

(a) Porifera

(b) Ctenophora

(c) Echinodermata

(d) Chordata

Answer: The correct option is (c) Echinodermata

The water vascular system is a characteristic feature of echinoderms, which helps in locomotion, respiration, and the capture of food.

Q9. "All vertebrates are chordates, but all chordates are vertebrates." Justify the statement.

Answer: Phylum Chordata contains animals that have a notochord, i.e., an elastic rod-shaped structure. Phylum Chordata is still divided into three sub-phyla: Urochordata, Cephalochordata, and Vertebrata. In vertebrates, the notochord is superseded by a vertebral column, but within urochordates and cephalochordates, there is no vertebral column present. Therefore, all vertebrates are chordates, but they are not necessarily vertebrates, as they can also be urochordates or cephalochordates.

Q10. How important is the presence of an air bladder in Pisces?

Answer: Osteichthyes (bony fishes, such as salmon) have an air bladder, which keeps them buoyant and prevents them from sinking in water. It makes them remain at a specific depth without swimming continuously. Chondrichthyes (cartilaginous fishes, such as sharks) do not have an air bladder. They need to swim continuously, employing their fins and body to remain afloat to avoid sinking.

The air bladder functions as a buoyancy support, whereas sharks survive using motion.

Q11. What are the modifications that are observed in birds that help them fly?

Answer: Birds have some adaptations that help them to fly:

• They have light bones with air-filled cavities, which lighten their load and reduce the effort of flying.
• A streamlined body cuts the resistance of the air, making it move smoothly through the air.
• Powerful flight muscles help in flapping the wings.
• The front limbs are modified into wings for flight, and the hind limbs are used for walking and perching.
• Additional air sacs in their bodies supply sufficient oxygen for extensive flights.
• These adaptations render birds ideally suited to flight.

Q12. Could the number of eggs or young ones produced by an oviparous and viviparous mother be equal? Why?

Answer: Oviparous creatures lay eggs outside the body and generally give birth to a greater number of offspring, as they are given little parental care and exposed to severe environmental conditions. Viviparous creatures, on the other hand, give birth to live offspring and offer care both pre- and post-birth. This greater parental care leads to greater survival rates, reducing the necessity for a high number of offspring. Thus, the number of eggs or young ones given birth to by oviparous and viviparous mothers is not the same.

Q13. Segmentation in the body is first observed in which of the following:

(a) Platyhelminthes

(b) Aschelminthes

(c) Annelida

(d) Arthropoda

Answer: The correct option is (c) Annelida

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: (a)-(viii), (b)-(v), (c)-(iv), (d)-(i), (e)-(ii), (f)- (vii), (g)- (iii), (h)- (vi)

Q15. Prepare a list of some animals that are found parasitic on human beings.

Answer:

• Taenia ( Tapeworm)
• Ascaris (roundworm)
• Ancylostoma (hookworm)
• Enterobius (pinworm)
• Wuchereria (filarial worm)

NCERT Solutions for Class 11: Subject-wise

• NCERT Solutions for Class 11 Maths
• NCERT Solutions for Class 11 Chemistry
• NCERT Solutions for Class 11 Physics

How to Solve Animal Kingdom Class 11 Question Answer?

The approach to solving questions of the Animal Kingdom chapter involves a clear understanding. Students can follow the steps given below:

• To understand the diversity of the animal kingdom, start with the classification of animals. Classification is based on features such as body symmetry, coelom, segmentation, etc.

• Go through all the terms like asymmetry, radial symmetry, and bilateral symmetry provided in the Class 11 Biology Animal Kingdom question answer.

• Prepare a table by writing down all the distinguishing features of phyla like Arthropoda, Mollusca, Chordata, etc.

• Study the features of these phyla using diagrams. Students can go through the Class 11 Biology Chapter 4 Animal Kingdom question answer, which helps them to remember their characteristics for a longer time.

• Try to solve a lot of questions from this chapter to gain confidence. Refer to the NCERT Solutions for Class 11 to get familiar with the pattern and difficulty level.

Main Topics of Class 11 Biology Chapter 4 Animal Kingdom

Classification of animals based on their body organisation, symmetry, and evolutionary relationships is covered in the chapter Animal Kingdom. Class 11 Biology Chapter 4 Animal Kingdom NCERT Solutions helps students understand the diversity of the animal world from simple organisms to complex chordates.

• Basis of Classification of Animals

• Levels of Organisation

• Body Symmetry

• Germ Layers

• Coelom

• Segmentation

• Notochord

• Classification of Non-Chordates - Porifera, Cnidaria, Ctenophora, Platyhelminthes, Nematoda, Annelida, etc.

Important Questions from NCERT Class 11 Biology Chapter 4 Animal Kingdom

Given below is a question from the Animal Kingdom chapter along with the answers. Focusing on the questions given in the NCERT Solutions for Class 11 Biology Chapter 4 Animal Kingdom helps to understand better.

Question 1: The following are the statements about non-chordates:
A. Gill slits perforate the pharynx.
B. Notochord is absent.
C. The central nervous system is dorsal.
D. Heart is dorsal if present.
E. Tail behind the body
Choose the most appropriate answer from the options given below:

1. A & C only

2. A, B & D only

3. B, D & E only

4. B, C & D only

Answer:

In invertebrates, the notochord, a defining feature of chordates, is absent, and their body structure is often supported by other means, like exoskeletons or hydrostatic skeletons. If a heart is present, it is typically located dorsally, unlike the ventral heart found in chordates. In addition, they lack a tail behind the body, which is a characteristic feature of chordates and plays a role in locomotion or balance in those organisms.

Hence, the correct answer is option 3, B, D & E only

Question 2: The body cavity is the cavity present between the body wall and the gut wall. In some animals, the body cavity is not lined by mesoderm. Such animals are called

1. Acoelomates

2. Pseudocoelomates

3. Coelomates

4. Haemo Coelomates

Answer:

Animals classified as pseudocoelomates have a fluid-filled bodily cavity known as a pseudocoelom that is not entirely lined by mesoderm tissue. The body cavity, the pseudocoelom, which divides the gut from the body wall, is situated between the mesoderm and the endoderm.
Hence, the correct answer is option 2, Pseudocoelomates

Question 3: Which one of the following sets of animals shares a four-chambered heart?

1. Amphibians, Reptiles, Birds

2. Crocodiles, Birds, Mammals

3. Crocodiles, Lizards, Turtles

4. Lizards, Mammals, Birds

Answer:

The heart is generally three-chambered in reptiles except crocodiles, which possess a four-chambered heart. The division in their heart is due to the incomplete interventricular septum in the ventricles. If we talk about the heart in birds and
mammals, it is four-chambered, and there is a complete division of the interventricular septum in the ventricles. Whereas, amphibians hold a three-chambered heart in which the ventricles are not separated; hence, two atria and one ventricle are present.
Hence, the correct answer is option 2, Crocodiles, Birds, Mammals

Question 4: In some animal groups, the body is divided into compartments with a serial repetition of at least some organs. This characteristic feature is called

1. Segmentation

2. Metamerism

3. Metagenesis

4. Metamorphosis

Answer:

The body in some animals is externally as well as internally separated into fragments with a serial repetition of at least some organs. This is called Metamerism. In other words, Metamerism is the condition of being constructed of a linear series of repeating parts. For example, in the earthworm, the body shows Metamerism.
Hence, the correct answer is option 2, Metamerism

Question 5: Given below are types of cells present in some animals. Which of the following cells can differentiate to perform different functions?

1. Choanocytes

2. Interstitial cells

3. Gastrodermal cells

4. Nematocytes

Answer:

Interstitial cells in the ovary and testes can differentiate. Interstitial cells refer to any cell that lies in the spaces between the functional cells of a tissue.
Hence, the correct answer is option 2, Interstitial cells

Question 6: Animals belonging to which of the following phyla possess a water vascular system?

1. Mollusca

2. Echinodermata

3. Cnidaria

4. Platyhelminthes

Answer:

A water vascular system is a unique characteristic feature of members of the Phylum Echinodermata. It helps in locomotion, food capture, and respiration. This system consists of fluid-filled canals and tube feet. No other phylum possesses this feature.

Hence, the correct answer is option 2, Echinodermata

Question 7: Which of the following is not a characteristic feature of the Phylum Arthropoda?

1. Jointed appendages

2. Chitinous exoskeleton

3. Closed circulatory system

4. Segmented body

Answer:

Arthropods have jointed appendages, a chitinous exoskeleton, and a segmented body. However, they possess an open circulatory system instead of a closed one. Therefore, closed circulation is not a characteristic of this phylum.

Hence, the correct answer is option 3, a closed circulatory system

Question 8: Which of the following phyla shows radial symmetry and a diploblastic level of organisation?

1. Porifera

2. Cnidaria

3. Annelida

4. Arthropoda

Answer:
Cnidarians exhibit radial symmetry and are diploblastic, meaning they have two germ layers - ectoderm and endoderm - with mesoglea in between. Porifera lack true tissues, while Annelida and Arthropoda are triploblastic and bilaterally symmetrical.

Hence, the correct answer is option 2, Cnidaria

Question 9: Which of the following animals is a triploblastic acoelomate?

1. Ascaris

2. Taenia

3. Earthworm

4. Cockroach

Answer:
Flatworms (Phylum Platyhelminthes) are triploblastic acoelomates, meaning they have three germ layers but no true body cavity. Taenia (tapeworm) belongs to this phylum. Ascaris is pseudocoelomate, while earthworm and cockroach are coelomates.

Hence, the correct answer is option 2, Taenia

What Students Learn from Animal Kingdom NCERT Solutions?

The Animal Kingdom chapter introduces students to the wide diversity of multicellular animals. It explains the classification, such as symmetry, level of organisation, body cavity, and mode of nutrition.

1. Students learn unique features and representative examples of each phylum from Porifera to Chordata.

2. It will clear the difference between chordates and non-chordates in easy language.

3. The Class 11 Biology Animal Kingdom question answer teaches about levels of organisation (cellular to organ-system), germ layers (diploblastic vs. triploblastic), and types of symmetry.

4. They will understand acoelomate, pseudocoelomate, and coelomate conditions, and the importance of segmentation in groups like Annelida and Arthropoda.

5. Students study open and closed circulatory systems, as well as the digestive systems, through the Animal Kingdom Class 11 question answer.

Why Class 11 Biology Chapter 4 Animal Kingdom NCERT Solutions are Important?

The chapter Animal Kingdom introduces students to a large variety of animals and explains on what basis these animals are classified. The solutions explain different levels of organisation, symmetry, germ layers, and other animal phyla, along with their characteristics and examples.

1. Class 11 Biology Chapter 4 Animal Kingdom NCERT Solutions allow students to understand the animal kingdom basis of classification criteria used.

2. The solutions also help them identify the features of major animal phyla, from Porifera to Chordata.

3. It improves understanding of how animals survive in different environmental conditions.

Students also get a clear knowledge of notochord, body segmentation, and germ layers.

What Extra Should Students Study Beyond the NCERT for NEET?

To do well in NEET, students should study extra topics and practice more beyond the NCERT. The extra topics that students have to study are given below. Along with this, they should practice the diagrams provided in the NCERT Solutions for Class 11 Biology Chapter 4 Animal Kingdom.

Chapter-Wise NCERT Solutions for Class 11 Biology

Below are the chapter-wise solutions by which students can easily understand all the concepts and perform well in the exams.