Multiple Choice Questions (MCQs): Animal Kingdom - NEET MCQ

The body of phylum Ctenophora bearseight external rows of ciliated comb plates, which help in locomotion

Line in NCERT: "The body bears eight external rows of ciliated comb plates, which help in locomotion."

Mode of nutrition, however, is not a primary basis for classification in the Animalia kingdom. While the mode of nutrition (how an organism obtains its food) is a crucial ecological and physiological trait, all animals are heterotrophic, meaning they rely on consuming other organisms for energy. The mode of nutrition might differentiate species within broader classifications based on their dietary preferences (e.g., herbivore, carnivore, omnivore), but it is not a foundational classification criterion like symmetry, segmentation, or levels of organization.

Line in NCERT: "The basic fundamental features such as level of organisation, symmetry, cell organisation, coelom, segmentation, notochord, etc., have enabled us to broadly classify the animal kingdom."

• Cells performing same functions group together to form a tissue.
• Organs are absent in this level of organization.
• Cells are specialized with division of labour.
• Example for this level of organization is Hydra.
• Planaria exhibits organ level of organization.

Line in NCERT: "In coelenterates, the arrangement of cells is more complex. Here the cells performing the same function are arranged into tissues, hence is called tissue level of organisation."

The most distinctive feature is the presence of water vascular system.

Line in NCERT: "The most distinctive feature of echinoderms is the presence of water vascular system which helps in locomotion, capture and transport of food and respiration."

• Tissue level of organization refers to the grouping of cells to form tissues that combine to form an animal body.
• There are no organs present in this level of organization.
• Example: Platyhelmenthes.

Line in NCERT: "Tissue level of organization refers to the way tissues combine to form organs which in turn form animal body."

Phylum Mollusca is the second largest phylum.

Line in NCERT: "This is the second largest animal phylum"

Swim bladder or air bladder is found only in bony fishes. It is a sac-like outgrowth from the dorsal wall of the oesophagus. It is hydrostatic in function and in some cases respiration as well. It provides bouncy to the fishes and helps them in swimming. Flying fish is bony fish, therefore present in them.

Line in NCERT: "Air bladder is present which regulates buoyancy."

All of them belong to Phylum Platyhelminthes and hence have dorso-ventrally flattened body and so, are called flatworms.

Line in NCERT: "They have dorso-ventrally flattened body, hence are called flatworms."

Endoskeleton is fully ossified (bony) and the long bonesare hollow with air cavities (pneumatic) in class aves.

Line in NCERT: "Endoskeleton is fully ossified (bony) and the long bones are hollow with air cavities (pneumatic)."

Poisonous snakes – Naja(Cobra), Bangarus(Krait), Vipera(Viper).

Book lung is a type of respiratory organ used for atmospheric gas exchange that is found in Arachnida such as scorpions and spiders.

Line in NCERT: "Respiratory organs are gills, book gills, book lungs or tracheal system."

The presence of mammary gland is a unique feature of class mammalia.

Line in NCERT: "The most unique mammalian characteristic is the presence of milk producing glands (mammary glands) by which the young ones are nourished."

Asterias does not have an excretory system.Asterias includes starfish or sea star. They are exclusively marine,

-  salamandra belong to class amphibia and amphibians have tympanum which represents ear and fertilisation is external.

-Pteropus belong to class mammalia, its skin possess hair and its viviparous. 

-Aurelia belong to phylum coelenterata,  coelenterates have cnidoblasts or cnidocytes (which contain the stinging capsules or nematocysts) present on the tentacles and the body. Cnidoblasts are used for anchorage, defense and for the capture of prey and Cnidarians exhibit tissue level of organisation. 

 -Ascaris belong to phylum aschelminthes and they aren’t segmented. But Sexes are separate (dioecious), i.e., males and females are distinct. Often females are longer than males. Fertilisation is internal and development may be direct (the young ones resemble the adult) or indirect.

• A digestive system with one opening to outside is called an incomplete digestive system and a digestive system with separate openings for ingestion and egestion is called complete digestive system.
• Platyhelmenthes and sea sponges have an incomplete digestive system.

Line in NCERT: "A complete digestive system has two openings, mouth and anus. Similarly, the digestive system in Platyhelminthes has only a single opening to the outside of the body that serves as both mouth and anus, and is hence called incomplete."

(i) is partially correct since Cyclostomes are primarily marine but also migrate to freshwater, Chondrichthyes are mostly marine, and Osteichthyes can be found in various aquatic environments.

(ii) is correct as Cyclostomes have a sucking mouth, Chondrichthyes have a ventral mouth, and Osteichthyes have a terminal mouth.

(iii) is correct as Cyclostomes have 6-15 pairs of gills, Chondrichthyes have 5-7 pairs of gills, and Osteichthyes have 4 pairs of gills.

(iv) is incorrect because Cyclostomes do not have scales, whereas Chondrichthyes have placoid scales, and Osteichthyes have cycloid/ctenoid or ganoid scales

Gregarious, polyphagous pest (a) refers to Locusta (iv), commonly known as locusts.
Adult with radial symmetry and larva with bilateral symmetry (b) describes Asterias (i), which is a starfish. Starfish have radial symmetry as adults but exhibit bilateral symmetry in their larval stages.
Book lungs (c) are found in Scorpions (ii), which use book lungs for respiration.
Bioluminescence (d) is exhibited by Ctenophora (iii), a type of comb jelly known for its bioluminescence.
Thus, the correct matching is:

Gregarious, polyphagous pest - Locusta (iv)
Adult with radial symmetry and larva with bilateral symmetry - Asterias (i)
Book lungs - Scorpion (ii)
Bioluminescence - Ctenophora (iii)
So the correct option is Option A.

Annelida: These animals (e.g., earthworms) have organ system level organization, bilateral symmetry, a true coelom, and body segmentation.

Arthropoda: These animals (e.g., insects, spiders) also exhibit organ system level organization, bilateral symmetry, a true coelom, and body segmentation.

Chordata: Chordates (e.g., vertebrates) possess all these features as well.

Option A: Mollusca (e.g., snails, clams) generally lack segmentation.

Option C: Mollusca lacks segmentation.

Option D: Mollusca again lacks segmentation.

Thus, the correct option is Option B: Annelida, Arthropoda, and Chordata.Topic in NCERT: Phylum – Annelida

Line in NCERT: "Annelids are metamerically segmented animals with a true coelom."

Porifera (sponges) have a body structure characterized by a meshwork of cells, internal cavities lined with flagellated cells (choanocytes) that filter food, and typically exhibit indirect development involving larval stages.
Coelenterata (Cnidaria) have a gastrovascular cavity and do not possess flagellated cells for filtering. They have both polyp and medusa stages with direct development.
Protozoa are single-celled organisms and do not have the complex body structures described.
Mollusca have complex body structures with organs and systems, and their development typically involves more direct development stages.
Thus, the correct option is Option A.Topic in NCERT: Phylum – Porifera (Sponges)

Line in NCERT: "Sponges reproduce asexually by fragmentation and sexually by formation of gametes. Fertilisation is internal and development is indirect having a larval stage which is morphologically distinct from the adult."