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Karnataka 1st PUC Biology Question Bank Chapter 4 Animal Kingdom
1st PUC Biology Animal Kingdom NCERT Text Book Questions and Answers
What are the difficulties that you would face in the classification of animals If common fundamental features are not taken into account?
If fundamental characters are not taken into account then the classification of animals is difficult due to difference in characters in different animals which are as follows:
- Grade of organisation
Common fundamental features help in grouping animals in certain categories or sub-categories. For example, all birds have forelimbs modified to assist in flying. This gives us one clue to categorise particular animals among aves.
If you are given a specimen, what are the steps that you follow to classify it?
The following features are used as the basis of animal classification.
- Level of Organization:- Identify the level of an organization like cellular, tissue, or a still higher level of Organization organ level of organization.
- Body symmetry: Identify if the animals are asymmetrical, radially, or have bilateral symmetry.
- Diploblastic of triploblastic:- based on the presence of a number of embryonic layers.
Diploblastic: two embryonic layers as external ectoderm and as internal
endoderm triploblastic: three embryonic layers as external ectoderm, middle mesoderm, and inner endoderm.
- Body cavity: The presence or absence of body cavity animals possessing coelom are called coelomates. Animals in which the body cavity absent are called acoelomates
- Segmentation: some animals show segmentation of the body externally or internally
- Presence of Notochord: chordates are animals with notochord and non-chordates which don’t form notochord during embryonic development.
How useful is the study of Body cavity and coelom in the classification of animals?
The presence or absence of a cavity between the body wall and the gut wall is very important is classification. The body cavity which is laid by mesoderm is called coelom. Animals possessing coelom are called coelomates (e.g.: annelids, mollusks, echinoderms, chordates etc.,)
In some animals, body cavity is not lined by mesoderm but mesoderm is present as scattered pouches in between the ectoderm and endoderm. Such a body cavity is called pseudocolor and animal pseudocoelomates.
The animals in which the body cavity is absent is called acoelomates
by the above example we can see that absence of coelom indicates that the animal is primitive, hence is classified as lower in the classification ladder, whereas coelomates are highly developed and pseudo coelomates are in middle of the classification ladder.
Distinguish between intracellular and extracellular Digestion?
|Intracellular Digestion||Extracellular Digestion|
|(a) Takes place in smaller animals (lower in classification) as food comprises only of basic molecules
(b) Digestion takes place within a cell i.e. a single cell is enough to carry out all digestive activities
(c) examples: porifera Coelenterataetc.,
|Takes place in highly developed organisms where there is a need for separate digestive tract.
A separate group of cells or tissues is necessary for the sole purpose of digestion
example: chordates, hemichordates, molluscs etc.
What is the difference between direct and indirect development?
In direct development young ones are formed directly from the development of the zygote whereas young ones are formed through an intermediate stage i.e. larval stage in the indirect development. There is no intermediate stage, indirect development and the young one resembles the adult.
What are the peculiar features that you find in parasitic Platyhelminthes?
Hooks and Suckers are present in parasitic Platyhelminthes. Some of them absorb nutrients from the host directly through their body surface, e.g.: Taenia (Tapeworm), Fasciola/liver fluke).
What are the reasons that you can think of for the Arthropoda to constitute the largest group of the Animal Kingdom?
Arthropods are the most successful group of animals on the earth. Their success is due to
- Unique chitinous cuticle
- Lightweight exoskeleton
- Omnivorous habit
- Mouthparts adapted to various modes of feeding like biting, chewing, sucking, etc.
- Adaptation to different climatic conditions.
Water Vascular system is the characteristic of which group of the following
“All vertebrates are chordates but all chordates are not vertebrates”. Justify the statement.
Phylum chordates include two subphyla
- Protochordates (urochordates and cephalochordates) or Acraniata
- Vertebrates or Craniata
All chordates have notochord present in some stage of life. In vertebrates, the notochord is present in the embryonic stage. This is replaced by a vertebral column during the adult stages.
This confirms that all vertebrates are chordates but all chordates are not vertebrates, they may be protochordate.
How important is the presence of Air bladder in Pisces?
The air bladder is a hydrostatic organ which regulates buoyancy. It also aids in swimming by reducing the weight of the body. Hence, this means that members of Pisces don’t have to keep on swimming to remain floating.
What are the modifications that are observed in birds that help them fly?
The forelimbs are modified into wings. The hind limbs generally have scales and are modified for walking, swimming, or clasping the tree branches. Skin is dry without glands except for the oil gland at the base of the tail. The endoskeleton is fully ossified (bony) and the long bones are hollow with air cavities.
Could the number of eggs of young ones by as Oviparous and viviparous mother be equal? Why?
The number of eggs given by oviparous and young ones given by viviparous animals is not equal because the egg-laying animals lay-more eggs to resist the environmental forces for survival so that the population remains constant or not declining while the viviparous animals nurture their young ones and give birth to less number of offsprings as parental care is shown in the viviparous animals.
Segmentation in the body is first observed in which of the following
Match the following
(a) operculum – (i) ctenophoran
(b) parapodia- (ii) Mollusca
(c) scales- (iii) porifera
d) comb plates – (iv) Reptilia
(e) Radula – (v) Annelida
(f) Hairs – (vi) Cyclostome and chondrichthyes
(g) Choanocytes – (vii) Mammalia
(h) cellists- (viii) Osteichthyes
a – viii
b – v
c – iv
d – i
e – ii
f – vii
g – iii
h – vi
Prepare a list of some animals that are found parasitic on human beings.
- Porktape worm solium
- Fasciola hepatica (liver fluke)
- Schistosoma (blood fluke)
- Wuchereria bancrafti (filarial worm)
- Ancylostoma duodenale (hook worm)
- Ascaris lumbricoides (The giant intestinal roundworm)
- boa loa (eyewonn)
- Trichinella spiralis (trichinia worm)
1st PUC Biology Animal Kingdom Additional Questions and Answers
1st PUC Biology Animal Kingdom One Mark Questions
Define the term Porifera?
Organisms bearing microscopic ‘pores’ on their body are called poriferans and belong to the phylum Porifera.
Which type of cells is unique to the sponge?
Choanocytes / Collar cells.
What is a canal system?
The body wall of sponges is folded to form intercommunicating cavities or canals for the entrance and exit of water called canal system.
Name the Larva of Sponges?
Amphibiastula or Parenchymula.
Name the glass rope Sponge?
What is the gastrovascular cavity?
The body cavity of coelenterates is called the coelenteron or gastrovascular cavity.
What are coral reefs?
Coral reefs are limestone formations, formed of the exoskeleton of stony corals. Example Madreporia.
Define the term Platyhelminthes?
The term Platyhelminthes refers to flatworms.
What are flame cells? Where do they oc¬cur? (B. North 2004)
Flame cells are the excretory organs of the phylum Platyhelminthes. They are found in excretory ducts/protonephridia.
What is Pseudocoel? Where does it occur?
The body of platyhelminths has a false cavity called Pseudocoel. It is not derived from the Mesoderm.
Give two examples of parasitic flatworms? (D. Kannada 2009)
Liver fluke – Fasciola hepatica Tapeworm – Taenia solium
Mention the functions of Flame cells. (B. North 2005)
Flame cells are the excretory organs of flatworms.
Define the term Arthropoda?
Organisms having jointed appendages are grouped in phylum Arthropoda.
What is Haemocoel? (B. North 2004)
Define Haemocoel (Hassan2005)
In Arthropods blood fills in the body cavity (coelom) called Haemocoel.
What is moulting or Ecdysis?
The exoskeleton Arthropods are dead and cannot grow. Therefore the old exoskeleton is thrown off and a new one is developed periodically which is known as Moulting / Ecdysis.
Name the various respiratory organs of phylum Arthropoda?
Body surface, gills, trachea, or Book lungs.
Name the phylum which consists of Pseudocoel?
Name the excretory organs of Aschelminthes.
Give one identifying feature of a male Ascaris?
Male ascaris has the presence of penial setae.
What are Eucoelomates?
Metazoans having a true body cavity (coelom) are called Eumetazoans.
What are Annelids?
Organisms having a segmented body are called Annelids.
What is Coelom? (Dharwar 2004)
The body cavity present between the body wall and the midgut in triploblastic animals is called Coelom. Or It is the cavity present between mesoderm and endoderm in triploblastic animals.
What do you mean by the term Mollusca?
The term Mollusca refers to soft-bodied organisms.
What is the mantle?
What is the function of the mantle? (Shimoga 04)
It is the fleshy outgrowth that covers the body of molluscans.
What is radula?
The radula is a file-like rasping organ which helps to feed in molluscans.
What is the die type of circulation in Mollusca?
Name the larva of Mollusca ?
What Are Echinoderms?
Spiny-skinned organisms are called Echinoderms.
What type of symmetry is present in Starfish? (Bijapur2004)
In which Phylum do you find the Ambulacral system? (Dharwar 2004, Shimoga 2006)
What are chordates?
Organisms having a notochord are called chordates.
What is a notochord?
The notochord is a cylindrical rod that supports the body of chordates.
What are Oesticthyes?
Bony fishes are called Oesticthyes
What are Poikilothermic organisms?
Blooded animals are called Poikilotherms. They cannot maintain constant body temperature.
What is Aestivation?
The process of having summer sleep by organisms is called Aestivation.
What Is hibernation?
The Winter sleep of animals is called Hibernation.
What is moulting? (Bangalore North 2004)
The process of shedding the scaly covering by Reptiles is called moulting.
What are pneumatised bones?
The hollow bones containing air sacs in birds are called Pneumatised bones.
Define the term Ratitae?
Flightless birds are called Ratitae.
Give one example for egg-laying mammals?
Platypus (Bangalore North 2004)
Mention the functions of Gills. (B. North 04)
Gills are the respiratory organs of fishes.
Name the type of nutrition that is characteristic of animals.
Name the phylum where animals have haemoglobin dissolved in the plasma.
What is parapodia?
Parapodia is a locomotory organ of Neries belonging to Annelida. It helps in swimming.
How is respiration carried out in annelids?
Respiration is carried out by the skin.
Name the largest phylum In the kingdom of Animals.
What is the name given to the fluid-filled body of the Arthropod?
1st PUC Biology Animal Kingdom Two Marks Questions
Explain the diploblastic body wall of sponges? (B’lore North, Belgaum 2004)
‘The body wall of sponges is made up of two germ layers. The outer layer is a pinacoderm formed of pinacocytes and the inner layer is a choanoderm formed of choanocytes. Between the two la /ers there is a gelatinous matrix called – Mesoglea.
What is Pseudocoelomata ? Give one example.
Organisms having a false coelom which is not derived from the mesoderm are called Psecudococlomates Example: Ascaris.
Name the respiratory organ present in an Arthropodan and an Amphibian. (B‘ North 05)
- Arthropods-gills or gill books in aquatic forms and tracheae or book lungs in terrestrial forms.
- Amphibians -Skin, gills, and lungs in the larvae & skin and lungs in adults.
Differentiate Urochordata and Cephalochordata with suitable examples for each.
Subphylum Urochordata is known as sea-squirts, adults are mostly marine and fixed, the body is covered by test/tunic, notochord & nerve cord are found in the larvae and are lost and reduced to a ganglion in the adult.
Sub-phylum Cephalochordata has a fish-like body, notochord and nerve cord are present throughout, eyes, nose, ears, and jaws are absent, but animal represents the fundamental plan of the chordate body in a simple form. Example: Amphioxus.
What are setae? Give their significance. (Tumkur2005)
Setae are chitinous hair-like bristles found embedded in the body wall of earthworm and aid locomotion.
How many chambers are present in an amphibia heart? Name them.
Amphibian heat has 3 chambers two auricles and one ventricle.
Differentiates between Chondrichthyes and Osteichthyes.
(a) The endoskeleton is cartilaginous
(a) The endoskeleton is bony
1st PUC Biology Animal Kingdom Three Marks Diagram
Draw a neat labelled diagram
1st PUC Biology Animal Kingdom Five Marks Questions
Discuss the special feature of sponges.
(Chikmagalur, Shimoga 2004)
Enumerate the general characters of the phylum Porifera. Give two examples. (Kolar 05)
The sponges belonging to the phylum Porifera exhibit the following features.
- Primitive multicellular Organisms with a cellular grade of Organisation.
- They are exclusively aquatic, largely marine, with very few freshwaters.
- The adult forms are sessile (attached) but the larval forms are free-swimming.
- The body is asymmetrical or radially symmetrical.
- The body wall is diploblastic with choanoderm (endoderm) and pinacoderm (ectoderm) and mesoglea in between.
- The body surface bears large numbers of microscopic processes called Dermal Ostia. The body cavity is called spongocoel which opens outside by Osculum.
- The spicules formed of calcium carbonate or silica form the internal skeletal support.
- Sponges reproduce by asexual, sexual, and by gemmule formation. The larvas of sponges is called Amphiblastula or Parenchymula. Examples: Scyon and Euspongia.
Discuss the identifying features of phylum cnidaria or Coelenterata? (B’North. 2004, U.Kannada 2008)
The organisms belonging to the phylum Cnidaria exhibit the following characters.
- They are primitive metazoans having tissue grades of organisation.
- They are aquatic both freshwater and marine, solitary or colonial with Radial symmetry.
- The body wall is diploblastic with outer ectroderm and inner endoderm. Ectoderm has specialised stinging cells called Nematocysts
- The body wall encloses a body cavity called the coelenteron or Gastrovascular cavity.
- Coelenterates exist in two forms in their life cycle. The asexual reproducing form is called polyp and the sexually reproducing form called Medusa. Thus they exhibit polymorphism.
- The polyp stage alternates with the medusa stage in coelectorates and is called Metagenesis.
- Respiratory, circulatory and excretory system are absent.
- Reproduction occurs both by asexual and sexual methods.
- Asexual reproduction is by budding arid sexual reproduction is by the production of Gametes.
List the important features of the phylum Platyhelminthes? (Dharwar 2004)
Write the general characters of the phylum Platyhelminthes. Mention three classes and give one example for each. (M.Q.P., D.K. 2005, Udupi 2006)
Phylum Platyhelminthes includes the flatworms which show the following characters.
- Multicellular organisms with organ grade of organisation.
- The body is bilaterally symmetrical and dorsoventrally flattened.
- The body wall is triploblastic with ectoderm, mesoderm, and endoderm forming the layers. The coelom is totally absent.
- The body is unsegmented and varies in shape. It may be elongated, flattened, ribbon-like or leaf-like.
- The parasitic forms are protected by a thick cuticle and bears, hooks, spines, or suckers for attachment.
- Digestive, circulatory, respiratory, and skeletal systems are absent.
- Excretion occurs by excretory cells called flame cells which form the protonephridia.
- The nervous system consists of nerve aggregations called ganglia.
- Sexes are mostly united (Hermaphrodites). Reproduction is by asexual and sexual methods. Development is indirect.
Class – Turbellaria Eg. lanaria
Class – Trematoda Eg. Fasciola hepatica
Class – Cestoda Eg. Taenia solium
Write the general characters of the phylum Aschelminthes. Mention any two examples.
(Bangalore Rural 2005)
- Body is bilaterally symmetrical and triploblastic. The body wall shows syncytial nature.
- Body is vermiform, cylindrical without a defi¬nite head.
- Cuticle is tough and resistant.
- The body cavity is a false coelom, (pseudocoelomate) and lies between the body wall and the digestive tract.
- Digestive system is complete with the mouth and anus.
- Circulatory & respiratory systems are absent.
- Sexes are always separate, exhibit sexual dimorphism, and show a Simple or complex life cycle.
- Excretory system shows a pair of longitudinal excretory canals with an excretory pore.
- Ascaris lumbricoides (roundworm)
- Ancylostoma duodenale (hookworm)
List out the salient features of phylum Annelida. (Bangalore Rural Q5, Bijapur 2004, Shimoga 2006, Tumkiir 2008) Mention any four characteristic features of phylum Annelida and give two examples. (D. Kannada, Koppala 2008)
- Members of Annelida are bilaterally symmetrical and triploblastic.
- Annelids exhibit true segmentation of the body. This is called metamerism. Metamerism means a linear division of the body into similar ring-like parts called segments (or somites or metameres) Segmentation is both external and internal.
- Each segment of the body possesses a set of muscles, ganglia, nerves, nephridia, gonads, etc.
- The body is soft, elongated, cylindrical or dorsoventrally flattened with head formation (cephalization) at the anterior end.
- The body appendages may be parapodia, or lateral bristles, or setae on each segment.
- The body wall consists of a thin cuticle secreted by the underlying single-layered epidermis. Below the epidermis, circular and longitudinal muscles are present.
- The body cavity is a true coelom, present between the body wall and gut. Coelom is lined with eoelomic epithelium derived from mesoderm.
- Digestive system is complete, straight, with mouth and anus.
- Circulatory system is closed type with heart and blood vessels. Blood is red with pigment hemoglobin found dissolved in plasma.
- Respiration is by the skin, gills or parapodia.
- Excretory organs consist of ciliated nephridia in most of the segments.
- Nervous system consists of a pair of dorsal cerebral ganglia forming the brain, connected to the sub-pharyngeal ganglia by a pair of connective. From the sub pharyngeal ganglion originates the double ventral nerve cord with segmental ganglion and nerves. (12) Sexes may be separate or united. Asexual reproduction by budding or fission. Development may be direct or indirect. When indirect a larval form called trochophore occurs. Examples:- Nereis & Hirudinaria.
Write the eight general characters of phylum Arthropoda. Mention any two examples.
(Bangalore North, Dharwar, Guibarga 2004, M.Q.P., Mandya, Tumkur 2005, D.K.2005,2010)
The characters of the phylum Arthropoda are
- Body is bilateral, triploblastic, and segmented into metameres.
- Body is externally covered by a thick protective chitinous cuticle forming an exoskeleton.
- Each body segment bears a pair of jointed appendages for locomotion.
- The exoskeleton is cast-off periodically by a process called moulting or Ecdysis.
- Body cavity is filled by blood and is called Haemocoel.
- Digestive System is complete.
- Respiration takes place either with gills, trachea or book lungs.
- Vascular system is open type. The hemolymph has the pigment Haemocyanin.
- Excretion occurs by Malpighian tubules (Insects) or by green glands.
- Development is direct or indirect. The larva undergoes metamorphosis into an adult. Examples are Periplaneta Americana (Cockroach) & Poecilocerus pictures (grasshopper).
List out the salient features of Phylum Mollusca. (D.Kannada2007, U.Kannada2008)
- Bilaterally symmetrical, triploblastic, Coelomate.
- Body is unsegmented, has different shapes, soft parts normally form the head, visceral mass, and ventral muscular part.
- Head bears sense organs like eyes, tentacles, visceral mass encloses organ systems and foot for locomotion.
- The mantle secretes a shell which may be external or internal, univalved/bivalved with two lateral pieces.
- The nervous system is composed of a series of ganglia interconnected by commissures and connectives.
List out the salient features of the phylum Echinodermata. Give two examples. (Kolar 05, Udupi 2008)
- Presence of pentamerous radial symmetry.
- They are coelomate with unsegmented.
- Triploblastic and characterized by an endoskeleton, body, varied in shape.
- Presence of the water vascular system with tube feet (ambulacral system).
- The circulatory system is of the open type.
- Examples: Sea urchin, Sea cucumber.
List out the general characters of class Reptilia. (Bangalore North 2004)
List any six salient features of class Reptilia. Give any two examples. (Bangalore Rural, Tumkur, Hassan 2005) OR List out the salient features of class reptiles. (D. Kannada 2007)
- Widely distributed. Warm-blooded (endothermic) or homeothermic vertebrates.
- The body is fusiform covered with feathers. Scales cover the hind limbs.
- Forelimbs are modified into wings. Whereas hind limbs consist of usually 4 toes and adapted for perching, walking or swimming.
- Adapted for aerial life. Lungs are the respiratory organs, they are connected to thin-walled air sacs.
- Skeleton is light and bones contain air cavities (pneumatized) skull is monocondylar as in reptiles.
- Voicebox is called syrinx which is situated at the base of the trachea.
- Heart is perfectly 4 chambered. There is a single aortic arch on the right side only. RBC are nucleated and biconvex.
- Kidneys are advanced type that is metanephric. Uric acid is the nitrogenous waste.
Sexes are separate. Ovary is single in female. Fertilization is internal. Oviparous laying eggs. Eggs contain much yolk. Eggs are covered by shell. Eggs hatch after a period of incubation by parents. Birds show high degree of parental care.
- Jaws are modified into beak. No living bird possesses teeth. Class Aves divided into sub class Archaeornithes and Neornithes. Living Birds are included under Neornithes which are classified into Ratitae and carinatae. Ratitae are flight less birds whereas carinatae are flying birds. Examples – snakes, lizards
Write the salient features of class Pisces. (Belgaum 2004)
- Fishes are cold-blooded vertebrates which are more completely adapted to aquatic life than any other vertebrates.
- The body is streamlined to facilitate locomotion through water.
- The skin is covered with scales, dermal denticles.
- Tail is muscular and is used for propulsion
- Two pairs of limbs are modified into fins provided with fin-rays. The main organ of locomotion is the tail.
- There are also median, and anal fins. They regulate swimming.
- Endoskeleton may be cartilaginous or bony
- The typical vertebra is amphicoelous or biconcave.
- The heart is two-chambered and contains only venous or deoxygenated blood.
- The respiration is done by gills associated with pharyngeal gill slits which are persistent throughout life.
- The olfactory lobes and cerebellum are generally well developed.
- The nostrils do not open into the pharynx because they are not having a respiratory function. There is neither external nor the middle ear but only the inner ear is present.
- Sexes are separate. Fertilization is internal or external. Oviparous or Viviparous, The development is without metamorphosis.
- The presence of lateral line sense organs and streamlined body is special characters.
- Accessory respiratory organs may be present.
- Embryonic membranes in the embryo stage are absent.
Write the salient features of class Mammalia with examples. (Gulbarga 2004, Gulbarga, Kolar, M.Q. P. 2005, D.K. 2005, 2010)
List out the features of class Mammalia. Give two examples for placental mammals. (Hassan, Bangalore South, Mandya, Mysore 05)
- Mammals possess mammary or milk glands to suckle the young ones.
- Mammals are warm-blooded animals with hairy covering on their body.
- The heart is four-chambered. There is only left aortic arch. The RBC are oval and nonnucleated.
- The skin has sweat and sebaceous glands.
- Limbs are of the pentadactyle type with claws, hoofs, nails etc.
- The bones of the skull are united with wavy lines called sutures.
- There is an external ear called the pinna and the internal ear consists of three ossicles i.e., incus, stapes and malleus.
- The brain is well developed. 4
- Teeth are present in sockets (thecodont) and modified for carrying out different functions in different groups of animals.
- Mammals possess a single bone (dentary) in their lower jaw.
- There is a muscular diaphragm separating the thorax and abdomen.
- Generally testes are present in the scrotal sacs. Male has a copulatory organ and female has clitoris.
- Viviparous except one group of mammal belonging to prototheria. Parental care is observed. The gestation period is found i.e., time taken for the complete development of the embryo. Parental care is of the utmost.
Class Mammalia is divided into three sub-classes.
- Prototheria (Monotremata) Example: Platypus, Echidna.
- Marsupialia (Metatherra) Example: Kangaroo, Koala Bear.
- Eutheria (Plaeentals) Example: Rabbit Cow, Tiger, Cat, Bat, Rat.
Differentiate between Cartilaginous fishes and Bony fishes. (B. North 2004, Hassan, D.K., Mandya 2005, D.Kannada, Udupi 2006)
Write any two differences between bony and cartilage fishes. (D. Kannada 2007)
- Cartilaginous fishes are found in marine water and estuaries, whereas, bony fishes are found in marine, fresh water, and brackish water.
- Endoskeleton is cartilage in Cartilaginous fishes, whereas, in bony fishes endoskeleton is made up of bones,
- In cartilaginous fishes placoid scales present in the skin, whereas, in bony fishes, scales are ganoid, ctenoid & cycloid.
- In cartilaginous fishes mouth and nostrils ventral in position, whereas, in bony fishes terminally situated.
- In cartilaginous fishes, gill slits 5-7 naked whereas, in bony fishes gills 4 covered by an operculum.
- There are no air bladder in cartilaginous fishes, whereas, in bony fishes air bladder present
- In cartilaginous fishes, claspers present in ‘ males, whereas, in bony fishes it is absent
- Cloaca present in cartilaginous fishes whereas, in bony fishes it is absent
- There is internal fertilization in Cartilaginous fishes, whereas, in bony fishes, it is mostly external fertilization.
List any six salient features of the class amphibia. Give two examples. –
(Udupi 2005, Tumkur 2008)
- They are aquatic or semi-aquatic i.e, amphibious and depend on water to lay eggs.
- Skin is naked, smooth, moist, rich in glands and highly vascular serving as an efficient res¬piratory organ.
- Skeleton is bony.
- Digestive system well developed, protrusible tongue and alimentary canal leads to the cloaca.
- Respiration may be through lungs, skin and by gills during the larval stage.
- Heart is 3 chambered, auricle completely divided, but mixing of blood in the ventricle. Examples- Frog, salamander.
(a) Bring out 4 differences between Nonchordata and Chordata. (D.K. 2006) Arts: Chordata
(a) These possess a notochord
(b) These have tubular nerve cord
(c) These have pharyngeal clefts.
(d) Eg: Horse
(a) Do not possess notochord.
(b) These do not have a tubular nerve cord.
(c) These do not have pharyngeal clefts.
(d) Eg: Jellyfish
(b) Mention the Subphylum of Chordata with suitable reason and an example for each.
- Subphylum Hemichordata – Example: Balanoglossus (includes worm-like protochordate)
- Sub phylum Urochordata – Example: Herdmania (includes sea-squirts, adults are marine and fixed, notochord and nerve cord and found only in the larvae)
- Sub phylum Cephalochordata – Example: Amphioxus (includes fish-like forms, eyes, jaws, nose, ears are absent, and the animal represents the fundamental plan of the Chordata body.
Describe the different levels of organisation of the body of the air mall, with an example for each.
- Cellular level: Here cells are arranged as loose cell aggregates.
- Tissue level: Here the cells performing the same function are arranged into tissues. eg: Hydra, Pleurobrachia
- Organ level: Here tissues are grouped together to form organs, each specialized for a particular function. eg: members of Platyhelminthes.
- Organ system: Organs have associated to form functional systems each system concerned with a specific physiological function. Eg: Arthropoda, Mollusca, Mammalia.