Chapter – 4 : Kingdom Animalia

5. Identify the animals given in pictures and write features of its phylum / class

(A.)

Ans:  The organism in the given picture is comb jelly and it belongs to phylum Ctenophora.

Features of phylum Ctenophora:
(1) Habitat: They are exclusively marine.
(2) Forms: They are free swimming animals.
(3) Germ layers: Members of this phylum are diploblastic.
(4) Body Symmetry: They are radially symmetrical.
(5) Body plan: The animals of this phylum show blind-sac body plan.
(6) Body organization: They show tissue level organization.
(7) Locomotion: It is carried out by eight rows of ciliated comb plates.
(8) Bioluminescence: It is the characteristic feature of the members of this phylum.
(9) Digestion: It is extracellular and intracellular.
(10) Reproduction: Reproduction is sexual with indirect development
(11) Colloblasts: These sticky cells are used to capture prey.
Eg. Pleurobrachia, Ctenoplana

(B.)

Ans: The organism in the give picture is Eel and it belongs to phylum Chordata.

Features of phylum Chordata :
(1) Notochord present at least in the early embryonic life.
(2) Nerve cord is single, dorsal and non-ganglionated.
(3) The heart is ventral in position.
(4) Pharyngeal gill slits are present at least in embryonic stage.
(5) Post-anal tail is present at least in embryonic stage.

(C) 

Ans: The given organism in this picture is Dolphin and it belongs to class Mammalia.

Features of class Mammalia:

(1) Special feature: Presence of mammary glands (milk producing glands) for the nourishment of young ones. Mammary glands are modified sweat glands.
(2) Habitat: Mammals are omnipresent (present everywhere). These are mostly terrestrial, some are aquatic and few are aerial and arboreal (living on trees).
(3) Locomotion: Limbs are the organs of locomotion and are modified for walking, climbing, burrowing. Swimming, etc.
(4) Body division: Body is differentiated into head, neck, trunk and tail. They have external ear.
(5) Body temperature: Mammals are homeotherms or warm-blooded animals.
(6) Exoskeleton: It is in the form of hair, fur, nails, hooves, horns, etc.
(7) Skin: Skin is glandular and has sweat glands and sebaceous (oil) glands.
(8) Mouth cavity: Mammals show heterodont dentition (various types of teeth like incisors, canines, premolars and molars).
(9) Circulation: Heart is ventral in position, four chambered with two auricles and two ventricles. RBCs are biconcave and enucleated (except camel). Blood is red in color.
(10) Respiration: Respiration takes place by lungs.
(11) Nervous system: Brain is highly developed. Cerebrum shows a transverse band called corpus callosum.
(12) Reproduction and development: Only few mammals are oviparous. e.g. Duck billed platypus. Some have pouches for development of immature young ones. These are called marsupials. e.g. Kangaroo. Most of the mammals are placental and viviparous.

(D)

Ans:- The given organism is  Snake and it belongs to class Reptiles.

Features of class Reptiles:
(1) Habitat: They are crawling animals. They are the first true terrestrial vertebrates. Few may be aquatic or semi-aquatic and are also found in marshy areas.
(2) Locomotion: Locomotion occurs by limbs in most animals. The limbs are pentadactyl with clawed digits, which help the animal to walk, creep or crawl. Snakes are limbless and crawl on their belly.
(3) Body temperature: They are poikilotherms.
(4) Exoskeleton: Skin is dry, non-glandular and covered by an exoskeleton of epidermal scales or scutes, shields or plates. Lizards and snake shed their skin periodically.
(5) Ear: Tympanum is present
(6) Circulatory system: It has two complete auricles but the ventricles are incompletely partitioned. Therefore, the heart of reptiles is not perfectly four chambered (except in crocodile the heart is four chambered).
(7) Nervous system: The brain is well developed. The olfactory lobes and cerebellum are better developed as compared to amphibians.
(8) Reproduction: Sexes are separate and exhibit prominent sexual dimorphism. Fertilization is internal and the animals are oviparous (exception – viper, it is viviparous). They show little parental care.

(E)

Ans:- The given organism is urchin and belongs to phylum Echinodermata.

Features of Phylum Echinodermata:
(1) Habitat: These are exclusively marine.
(2) Forms: Members of this phylum are solitary, sedentary or free-living and gregarious, benthic.
(3) Body symmetry: These animals are radially symmetrical with pentamerous symmetry.
(4) Shape: Members of Echinodermata are spherical, elongated or star shaped.
(5) Body: The endoskeleton is made up of calcareous ossicles. Spines are formed on the body. Hence, they are known as echinoderms. The body has two sides oral and aboral and lacks definite divisions. Mouth is ventrally present on oral surface and anus on aboral surface.
(6) Water vascular system: Presence of water vascular system is the peculiar character of echinoderms. Madreporite is the opening of water vascular system through which water enters. Water vascular system is useful in locomotion, food capturing, respiration.
(7) Digestion: Digestive system is complete.
(8) Respiration: Peristomial gills, papillae, respiratory tree, ete. are used for respiration.
(9) Circulatory and excretory systems: Absent in echinoderms.
(10) Nervous system: Nervous system is simple with a nerve ring around the mouth and radial nerves in arms.
(11) Reproduction and development: Sexes are separate (sometimes bisexual). Fertilization is external Development is indirect, i.e. through larval stages They show high power of regeneration.

(F) 

Ans: The given organism is flying lizard and belongs to class Reptiles.

Features of Class Reptiles:

(1) Habitat: They are crawling animals. They are the first true terrestrial vertebrates. Few may be aquatic or semi-aquatic and are also found in marshy areas.
(2) Locomotion: Locomotion occurs by limbs in most animals. The limbs are pentadactyl with clawed digits, which help the animal to walk, creep or crawl. Snakes are limbless and crawl on their belly.
(3) Body temperature: They are poikilotherms.
(4) Exoskeleton: Skin is dry, non-glandular and covered by an exoskeleton of epidermal scales or scutes, shields or plales. Lizards and snake slhed their skin perioditally.
(5) Ear: Tympanum is present
(6) Circulatory system: It has two complete auricles but the ventricles are incompletely partitioned. Therefore, the heart of reptiles is not perfectly four chambered (except in crocodile the heart is four chambered).
(7) Nervous system: The brain is well developed. The olfactory lobes and cerebellum are better developed as compared to amphibians.
(8) Reproduction: Sexes are separate and exhibit prominent sexual dimophism. Fertilization is internal and the animals are oviparous (exception – viper, it is viviparous). They show little parental care.

(G)

Ans: The give organism is Herdmania and belongs to Phylum Chordata.

Features of Phylum Chordata:

(1) Presence of hollow, dorsal nerve chord, running throughout the length of the body.
(2) Habitat: They are exclusively marine.
(3) Body covering: Soft body is covered by ‘test or ‘tunic which is made up of tunicine.
(4) Notochord: Notochord is present only in the tail of the larva and is lost during metamorphosis. Hence, the name Urochordata.
(5) Respiration: Pharynx with many gill slits for respiration.
(6) Circulation: Closed circulatory system is present.
(7) Reproduction: Development is indirect.
eg.  Herdmania. Salpa. Doliolum. Ascidia.

(H)

Ans : The organism in this picture is Nautilus and it belongs to phylum Mollusca.

Features of Phylum Mollusca:

(1) Habitat: They are aquatic or seen in marshy places. Few of them are terrestrial.
(2) Forms: Molluscs are either free-living or sedentary.
(3) Body plan: These are soft bodied and show tube within a tube type of body plan.
(4) Body symmetry: Most of the Molluscs show bilateral symmetry but few are asymmetrical due to torsion.
(5) Body division: Body consists of head, foot and visceral mass. Visceral mass is enclosed in thick, muscular fold of body wall called mantle. Mantle secretes a hard-calcareous shell, that may be external or internal or absent. Muscular foot is present ventrally.
(6) Digestive system: Digestive system is well-developed and complete with anterior mouth and posterior anus. Buccal cavity has a rasping organ called radula (helps in feeding), which is provided with transverse rows of teeth.
(7) Respiration: In aquatic forms, numerous feather-like gills called ctenidia, help in aquatic respiration. Terrestrial forms may show the presence of lungs.
(8) Circulatory system: Circulatory system is of open type (except in Sepia, where it is of the closed type). Blood contains a copper containing blue coloured respiratory pigment called haemocyanin.
(9) Excretion: Excretion occurs by kidney like structures, also called ‘Organ of Bojanus’.
(10) Nervous system and sense organs: Nervous system has three pairs of ganglia. All these ganglia are interconnected by commissures and connectives.
(11) Sense organs: Sense organs such as eyes for vision, tentacles for tactile sensation and osphradia for testing purity of water is present.
(12) Sexual reproduction: Sexes are usually separate. Animals of this phylum are mostly oviparous and the development is direct or indirect.

(I)

Ans :- The organism in this picture is Amphioxus its belongs to phylum Chordata (Subphylum Cephalochordata).

Features of phylum Chordata (Subphylum Cephalochordata):

(1) Cephalochordates are also known as lancelets and are small fish-like animals that rarely exceed 5 cm in length.
(2) Lancelets are exclusively marine and live partly buried in soft marine sediments.
(3) Notochord extends throughout entire length of the body and persists throughout life.
(4) Myotomes (muscle blocks) are present.
(5) Post anal tail is present.
(6)  Circulatory system is closed type. Blood lacks pigment.
eg. Branchiostoma