Test: Animal Kingdom - 1

• The body of annelids is segmented. Annelids are triploblastic (three germ layers present) and possess a true coelom.
• The coelom is the fluid-filled body cavity present between the gut wall and body wall.
• Some of the examples of annelids are earthworms, leeches, etc.

Fig: Phylum Annelida

Hence, the correct option is B.
NCERT Reference: Topic “4.2.6 Phylum – Annelida” of chapter 4 of NCERT.

Choanocytes are specialized cells that are found in sponges, which are multicellular animals belonging to the phylum Porifera. Choanocytes have a distinct structure that resembles a collar, which is why they are also commonly referred to as "collar cells."

• The term "flagellated cells" (option A) is not a correct synonym for choanocytes, as not all flagellated cells are choanocytes.
• "Amoeboid cells" (option C) and "epidermal cells" (option D) are also incorrect because they refer to different types of cells with different structures and functions in other contexts, and they are not synonyms for choanocytes.
• The most appropriate and commonly used term for choanocytes is "collar cells" (option B) due to their characteristic collar-like structure.

Hence, the correct option is B.

NCERT Reference: topic “4.2.1 Phylum – Porifera” of chapter 4.

Ichthyophis is a species of caecilians; the limbless amphibians usually observed in Southeast Asia, the western Indo-Australian Archipelago, and the southern Philippines.

At first look, this animal seems to be an earthworm. This is the class that has an aquatic larval degree and a mundane grown-up phase.

Hence, the correct option is A.

NCERT Reference: topic “4.2.11.4 Class – Amphibia” of chapter 4 of NCERT.

• The insects belong to phylum Arthropoda and hence, the excretory organ is Malphighian tubules.
• Malphighian tubules are the main excretory organs in insects. They are a part of the insect digestive system and play a crucial role in maintaining the insect's internal balance of water and ions, as well as in excreting waste products from the body.

Fig: Malphighian tubules

• Option A, Proboscis gland, is not a correct answer as proboscis is a specialized mouthpart in certain insects, such as butterflies and mosquitoes, used for feeding, and it is not involved in excretion.
• Option C, Gills, are respiratory organs found in aquatic insects, but they are not the main excretory organs.
• Option D, Excretory pore, is not a correct answer as it refers to a small opening in some insects that is used for excretion, but it is not an organ.
• Proboscis gland, gills and excretory pore are not the part of phylum Arthropoda.

Hence, the correct option is B.
NCERT Reference: Topic “4.2.7 Phylum – Arthropoda” of chapter 4 of NCERT.

Metamerism: In some animals, the body is externally and internally divided into segments with a serial repetition of at least some organs.

For example, in earthworm, the body shows this pattern called metameric segmentation and the phenomenon is known as metamerism or true segmentation. Metamerism is found in 3 animal phylums - Annelida, Arthropoda and Chordata.

Fig: Metamerism in Earthworm

Hence, the correct option is C.
NCERT Reference: Page no. 48 of topic “4.1.5 Segmentation” of chapter 4 of NCERT.

• Animals possessing coelom are called coelomates, e.g.,annelids, molluscs, arthropods, echinoderms, hemichordates and chordates.
• These are the animals in which there is no cavity present. The most common example is Platyhelminthes known as acoelomates.

Hence, the correct option is D.

NCERT Reference: topic “4.1.4 Coelom” of chapter 4 of NCERT.

The members of class Chondrichthyes are marine animals with streamlined body and have cartilaginous endoskeleton.

• Option D, Chondrichthyes are a class of fish that includes species such as sharks, rays, and skates. One of the defining characteristics of Chondrichthyes is that they possess a skeleton made of cartilage, which is a flexible and lightweight material, as opposed to the bony skeleton found in most other vertebrates, including mammals, reptiles, and chordates.
• Option A, Reptilia possess a 3-chambered heart with incompletely divided ventricle, is not a correct answer as reptiles, such as snakes, lizards, and turtles, generally possess a 3-chambered heart with a partially divided ventricle, which allows mixing of oxygenated and deoxygenated blood. However, there are some exceptions among reptiles, such as crocodiles, which possess a 4-chambered heart with completely divided ventricles.
• Option B, Mammalia give birth to young ones, is not a correct answer as there are some mammals, such as monotremes like platypus and echidna, that lay eggs instead of giving birth to live young.
• Option C, Chordates possess a mouth with an upper and lower jaw, is not a correct answer as not all chordates possess jaws. Jawless fish, such as lampreys and hagfish, which are also chordates, do not possess jaws.

Hence, the correct option is D.
NCERT Reference:  topic “4.2.11.2 Class – Chondrichthyes” of chapter 4 of NCERT.

• Air bladder provides buoyancy to the aquatic animals thus helps them to stay at the current water depth without having to waste energy in swimming.
• It is found in many bony fishes but not in cartilaginous fishes. Shark being a cartilaginous fish, does not possess air bladder.

Hence, the correct option is B.
NCERT Reference: topic “4.2.11.2 Class – Chondrichthyes” of chapter 4 of NCERT.

• Locust (Locusta) is a gregarious pest belonging to the phylum Arthropoda.
• Whereas economically important insects are – Apis (Honey bee), Bombyx (Silkworm), Laccifer (Lac insect). 

Fig: Image of Locust

Hence, the correct option is A.

NCERT Reference: Page no. 53 of topic “4.2.7 Phylum – Arthropoda” of chapter 4 of NCERT.

• The larvae of urochordates are called tadpole larvae.
• This larva is free-swimming and exhibits all chordate characteristics.
• It has a notochord, a dorsal nerve cord, pharyngeal slits and a post-anal tail.

Hence, the correct option is B.

NCERT Reference: Topic “4.2.11 Phylum – Chordata” of chapter 4 of 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.

Hence, the correct option is A.
NCERT Reference: Page no. 46 of topic “4.1.1 Levels of Organisation” of chapter 4 of NCERT.

• Cleidoic egg is the term which is used to refer to any closed egg of a land animal. It is also known as amniotic egg, because it occurs peculiarly in amniotes.
• It is laid by aves and reptiles. It involves internal fertilization because the eggs are laid on land, internal fertilization is needed and thus development occurs after laying the eggs externally.

Hence, the correct option is D.
NCERT Reference: Page no. 58 of topics “4.2.11.5 Class – Reptilia” and “4.2.11.6 Class – Aves” of chapter 4 of NCERT.

• Symmetry is an attribute of an organism showing regularity in body parts on a plane or around an axis.
• In Phylum Echinodermata, the adult echinoderms are radially symmetrical but the larvae are bilaterally symmetrical. 

Hence, the correct option is B.

NCERT Reference: Page no. 54 of topic “4.2.9 Phylum – Echinodermata” of chapter 4 of NCERT.

The animal is identified as Euspongia which belongs to phylum Porifera.

Hence, the correct option is C.
NCERT Reference: Page no. 49 of topic “4.2.1 Phylum – Porifera” of chapter 4 of NCERT.

• The name Porifera comes from the pores present on the surface of sponges.
• A hard and protective skeleton made up of sponging or spicules supports the body.
• Development of embryo takes place through an intermediate larval stage.
• The digestive system in Porifera is absent.

Hence, the correct option is D.

NCERT Reference: Page no. 49 of topic “4.2.1 Phylum – Porifera” of chapter 4.

• Planaria belongs to phylum Platyhelminthes.
• These are flatworms and has acoelomate body plan.
• It has three-layered body wall which includes ectoderm, endoderm, and mesoderm. 
• Acoelomates lack a body cavity, and instead the space between the body wall and the digestive tract is filled with muscle fibres and loose tissue called parenchyma.
• It acts as a skeletal support, nutrient storage, motility, reserves of regenerative cells and transporting materials.

Hence, the correct option is D.
NOTE: This question is knowledge and understanding based.

The zoological name of fresh water sponge is Spongilla.

Fig: Image of Spongilla

Hence, the correct option is D.
NCERT Reference: Page no. 50 of topic “4.2.1 Phylum – Porifera” of chapter 4 of NCERT.

Class-Cyclostomata is comprised of  the living jawless fishes. Their mouth is circular and lack jaws, hence they are also called agnathans.  It is surrounded by tentacles (e.g., lampreys and hellish). These also possess retractable teeth.

Fig: Class of Cyclostomata

Hence, the correct option is B.
NCERT Reference: Page no. 56 of topic “4.2.11.1 Class – Cyclostomata” of chapter 4 of NCERT.

Saccoglossus belongs to phylum Hemichordata and hence the excretory organ is proboscis gland.

NCERT Reference: Page no. 54 of topic “4.2.10 Phylum – Hemichordata” of chapter 4 of NCERT.

• Tissue level of organization is present in Coelenterata.
• Sea anemone exists in colonies.
• Coelenterates have two layers of cells in their body i.e. they are diploblastic.
• They have an incomplete digestive system.

Hence, the correct option is D.
NCERT Reference: Page no. 50 of topic “4.2.2 Phylum – Coelenterata (Cnidaria)” of chapter 3.

• The property of emitting light from a living organism is called bioluminescence.
• This is a notified property in case of Ctenophores which are also called Comb jellies or sea walnuts.

Hence, the correct option is D.

NCERT Reference: Page no. 51 of topic “4.2.3 Phylum – Ctenophora” of chapter 4.

• Limulus polyphemus or Atlantic horseshoe crab are considered 'living fossils' as they haven't undergone obvious morphological changes in comparison with Carboniferous and Triassic fossil forms.
• Moreover, they are the only ones that survived different extinction events.

Fig: Limulus

Hence, the correct option is A.
NCERT Reference: Page no. 53 of topic “4.2.7 Phylum – Arthropoda” of chapter 4 of NCERT.

Platypus is oviparous as it is an egg-laying mammal. Rest three are viviparous mammals.

Hence, the correct option is A.
NCERT Reference: Page no. 60 of topic “4.2.11.7 Class – Mammalia” of chapter 4 of NCERT.

Reptiles generally possess three chamber heart, two upper chamber and single lower chamber. But in crocodile, the heart is four chambered having two atrium and two ventricles.

Hence, the correct option is C.
NCERT Reference: Page no. 58 of topic “4.2.11.5 Class – Reptilia” of chapter 4 of NCERT.

• Statement A says that in ctenophores, locomotion is mediated with help of comb plates. The body of ctenophores bears eight rows of comb plates externally. These plates are lined with fine cilia or hair-like structures that mediate movement. The presence of cilia gives these plates a comb-like appearance. So, this statement is correct.
• Statement B says that in cockroaches and prawns the excretory organ is the same and that is Malpighian tubules. Excretion refers to waste removal from the body. Each organism has different organs and ways to remove waste. Cockroaches being an insect excrete using malpighian tubules. On the other hand, a prawn is a crustacean. It excretes using green glands that help in the removal of nitrogenous waste from its body. Thus, this statement is incorrect.
• Statement C is that in Fasciola, flame cells take part in excretion. The flame cells in Fasciola are modified versions of mesenchymal cells. Each flame cell consists of cilia. These cells vibrate like the flickering of a flame. As they vibrate they help in waste removal from the Fasciola body. Thus, this statement is also correct.
• Statement D says that earthworms are hermaphrodites still they are capable of cross-fertilization. Earthworms are indeed hermaphrodites. This means that they have both the female and male sex organs in their body. They can self fertilize and produce off-springs. But as they have both types of sex organs, they can produce female as well as male gametes. This allows them to take or give gametes and perform cross-fertilization. So, this statement is correct.

Hence, the correct option is B.
NCERT Reference: Page no. 53 of topic “4.2.7 Phylum – Arthropoda” of chapter 4 of NCERT.