Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

Tamilnadu State Board New Syllabus Samacheer Kalvi 11th Bio Zoology Guide Pdf Chapter 2 Kingdom Animalia Text Book Back Questions and Answers, Notes.

Tamilnadu Samacheer Kalvi 11th Bio Zoology Guide Chapter 2 Kingdom Animalia

11th Bio Zoology Guide Kingdom Animalia Text Book Back Questions and Answers

Part I

I. Choose The Best Options

Question 1.
The symmetry exhibited in cnidarians is
a. Radial
b. Bilateral
c. Pentamerous radial
d. Asymmetrical
Answer:
a. Radial

Question 2.
Sea anemone belongs to phylum
a. Protozoa
b. Porifera
c. Coelenterata
d. Echinodermata
Answer:
c. Coelenterata

Question 3.
The excretory cells that are found in platyhelminthes are
a. Protonephridia
b. Flame cells
c. Solenocytes
d. All of these
Answer:
b. Flame cells

Question 4.
In which of the following organisms, self fertilization is seen.
a. Fish
b. Round worm
c. Earthworm
d. Liver fluke
Answer:
d. Liver fluke

Question 5.
Nephridia of Earthworms are performing the same functions as
a. Gills of prawn
b. Flame cells of Planaria
c. The trachea of insects
d. Nematoblasts of Hydra
Answer:
b. Flame cells of Planaria

Question 6.
Which of the following animals has a true coelom?
a. Ascaris
b. Pheretima
c. Sycon
d. Taenia solium
Answer:
b. Pheretima

Question 7.
Metameric segmentation is the main feature of
a. Annelida
b. Echinodermata
c. Arthropoda
d. Coelenterata
Answer:
a. Annelida

Question 8.
In Pheretima locomotion occurs with the help of
a. circular muscles
b. longitudinal muscles and setae
c. circular, longitudinal muscles and setae
d. parapodia
Answer:
c. circular, longitudinal muscles and setae

Question 9.
Which of the following have the highest number of species in nature?
a. Insects
b. Birds
c. Angiosperms
d. Fungi
Answer:
a. Insects

Question 10.
Which of the following is a crustacean?
a. Prawn
b. Snail
c. Sea anemone
d. Hydra
Answer:
a. Prawn

Question 11.
The respiratory pigment in cockroach is
a. Haemoglobin
b. Haemocyanin
c. Heamoerythrin
d. None of the above
Answer:
d. None of the above

Question 12.
Exoskeleton of which phylum consists of chitinous cuticle?
a. Annelida
b. Porifera
c. Arthropoda
d. Echinodermata
Answer:
c. Arthropoda

Question 13.
Lateral line sense organs occur in
a. Salamander
b. Frog
c. Water snake
d. Fish
Answer:
d. Fish

Question 14.
The limbless amphibian is
a. Icthyophis
b. Hyla
c. Rana
d. Salamander
Answer:
a. Icthyophis

Question 15.
Four chambered heart is present in
a. Lizard
b. Snake
c. Scorpion
d. Crocodile
Answer:
d. Crocodile

Question 16.
Which of the following is not correctly paired?
a. Humans – Ureotelic
b. Birds – Uricotelic
c. Lizards – Uricotelic
d. Whale – Ammonotelic
Answer:
d. Whale – Ammonotelic

Question 17.
Which of the following is an egg laying mammal?
a. Delphinus
b. Macropus
c. Ornithorhynchus
d. Equus
Answer:
c. Omithorhynchus

Question 18.
Pneumatic bones are seen in
a. Mammalia
b. Aves
c. Reptilia
d. Sponges
Answer:
b. Aves

Question 19.
Match the following columns and select the correct option.

Column -I	Column – II
(p) Pila	(i) Devil fish
(q) Dentalium	(ii) Chiton
(r) Chaetopleura	(iii) Apple snail
(s) Octopus	(iv) Tusk shell

a. p – (ii), q – (i), r – (iii), s – (iv)
b. p – (iii), q – (iv), r – (ii), s – (i)
c. p – (ii), q – (iv), r – (i), s – (iii)
d. p – (i), q – (ii), r – (iii), s – (iv)
Answer:
b. p – (iii), q – (iv), r – (ii), s – (i)

Question 20.
In which of the following phyla, the adult shows radial symmetry but the larva shows bilateral symmetry?
a. Mollusca
b. Echinodermata
c. Arthropoda
d. Annelida
Answer:
b. Echinodermata

Question 21.
Which of the following is correctly matched?
a. Physalia – Portuguese man of war
b. Pennatula – Sea fan
c. Adamsia – Sea pen
d. Gorgonia-Sea anemone
Answer:
a. Physalia – Portuguese man of war

Question 22.
Why are spongin and spicules important to a sponge?
Answer:
Spongin and spicules provide support and support to the soft body parts of the sponges. The spicules give the sponges rigidity and form to the sponges.

Question 23.
What are the four characteristics common to most animals?
Answer:

1. Cellular structure
2. The nature of coelom ;
3. Notochord
4. Segmentation or absence of segmentation.

Question 24.
List the features that all vertebrates show at some point in their development.
Answer:
All vertebrates possess notochord during the embryonic stay. li is repLaced by vertebra) column. All vertebrates possess pained appendages such as fins or lunits. Skin is covered by a protective skeleton comprising of scales. feathers hairs, claws, nails, etc. Respiration is aerobic through gills, skin. buccopharyngeal cavity’ and lungs. All vertebrates have a muscular heart with two, three, or four chambers and kidneys for excretion and osmoregulation.

Question 25.
Compare closed and opened circulatory system
Answer:

Open Circulation	Closed Circulation
1. There are no blood vessels	Presence of blood vessels.
2. Blood remains filled in the tissue spaces.	Blood is circulated through blood vessels
3. (Eg.) Arthropods, Mollusca, Echinodermata	(Eg.) Earthworm, Cephalochordates, Chordates

Question 26.
Compare Schizocoelom with enterocoelom
Answer:

Schizocoelomate	Enterocoelomate
1. Body cavity is formed by splitting of mesoderm.	The body cavity is formed from the mesodermal pouches or archenterons.
2. (Eg.) Annelids, Arthropods	(Eg.) Echinodermata Chordates

Question 27.
Identify the structure that the archenteron becomes in a developing animal.
Answer:
The archenteron becomes the cavity of the digestive tract.

Question 28.
Observe the animal below and answer the following questions
a. Identify the animal
b. What type of symmetry does this animal exhibit?
c. Is this animal Cephalized?
d. How many germ layers does this animal have?
e. How many openings does this animal’s digestive system have?
f. Does this animal have neurons?
Answer:
a) Sea anemone
b) Bilateral symmetry
c) It is not a cephalized animal
d) Diploblastic animal
e) One
f) Yes.

Question 29.
Choose the term that does not belong in the following group and explain why it does not belong?
Answer:

• Notochord, cephalization, dorsal nerve cord, and radial symmetry.
• Notochord, cephalization, and dorsal nerve cord are the characteristic features of chordates. The radial symmetry is not a characteristic feature of chordate. It is the feature of cnidarian and adult echinoderms. Hence it does not belong to the group.

Question 30.
Why flatworms are called acoelomates?
Answer:
The body cavity is formed from mesoderm but in flatworms, there is nobody cavity their body is solid with a perivisceral cavity.

Question 31.
What are flame cells?
Answer:
Flame cells are the specialized excretory cells in flat worms. They help in excretion and osmoregulation.

Question 32.
Concept Mapping – Use the following terms to create a concept map that shows the major characteristic features of the phylum Nematoda: Roundworms, pseudocoelomates, digestive tract, cuticle, parasite, sexual dimorphism
Answer:

Question 33.
In which phyla is the larva trochophore found?
Answer:
Trochopore larva is seen in the Phylum – Annelida.

Question 34.
Which of the chordate characteristics do tunicates retain as adults?
Answer:
Ventral and tabular heart. Respiration is through gill slits.

Question 35.
List the characteristic features that distinguish cartilaginous fishes from living jawless fishes.
Answer:

Cyclostomata	Chondrichthyes
1. Some are ectoparasites on some fishes.	They are free living.
2. Body is slender and eel-like	Skin is tough and covered with placoid scales
3. 6 to 15 pairs of gillslits for respiration.	Respiration is by lamelliform gills.
4. Mouth is circular without jaws and suctorial.	There are lower and upper jaws.
5. Migrate to freshwater for spawning	There is no migration during breeding.
6. After spawning they die	They don’t die after spawning
7. Oviparous	Oviparous, viviparous and Ova viviparous

Question 36.
List three features that characterize bony fishes.
Answer:

1. These fishes have a bony endoskeleton.
2. The skin is covered by ganoid, cycloid or ctenoid scales.
3. Gills are covered by an operculum.
4. They are ammonotelic.
5. They have mesonephric kidneys.
6. External fertilization is seen.

Question 37.
List the functions of air bladder in fishes.
Answer:

• Air bladder may be connected to the gut or not.
• They help in gaseous exchange.
• In ray-finned fishes, they help in buoyancy.

Question 38.
Write the characteristics that contribute to the success of reptiles on land.
Answer:

• The characteristics that contribute to the success of reptiles on land are as follows:
• The presence of dry and cornified skin with epidermal scales or scutes prevents the loss of water.
• The presence of metanephric kidney.
• They are uricotelic (they excrete uric acid to prevent the loss of water).

Question 39.
List the unique features of a bird’s endoskeleton.
Answer:

• The endoskeleton is fully ossified.
• The long bones are hollow with air cavities. So that they can easily fly with lesser weight.

Question 40.
Could the number of eggs or young ones produced by an oviparous and viviparous female be equal? Why?
Answer:
No. The number of eggs or young ones produced by an oviparous and viviparous female cannot be equal. When the oviparous animals lay eggs in the external environment or in the medium, the chance of survival and successful development into the adults are not certain. But in the case of viviparous animals, young ones are nurtured by the adult animals. Hence, oviparous animals lay more eggs if they are fertilized in the medium or in water.

Part-II

11th Bio Zoology Guide Kingdom Animalia Additional Important Questions and Answers

I. Choose The Best Options

Question 1.
Which of the following has loose aggregates of cells without tissues?
(a) cnidarians
(b) flatworms
(c) sponges
(d) echinodenns
Answer:
(c) sponges

Question 2.
Name the organs formed from ectoderm.
a. Heart
b. Hair
c. Muscle
d. Intestine
Answer:
b. Hair

Question 3.
Which of the following is advantageous for the animals in locomotion, food capture etc.?
(a) asymmetrical
(b) radially symmetrical
(c) biradially symmetrical
(d) bilaterally symmetrical
Answer:
(d) bilaterally symmetrical

Question 4.
Inporiferans through ………………. pores water enters into the body and goes out through.
a. Osculum Ostia
b. Ostia Osculum
c. Mouth Ostia
d. Mouth Osculum
Answer:
b. Ostia Osculum

Question 5.
Radiata include
(a) Diploblastic and bilaterally symmetrical animals
(b) Triploblastic and radially symmetrical animals
(c) Diploblastic and radially symmetrical animals
(d) Triploblastic and bilaterally symmetrical animals
Answer:
(c) Diploblastic and radially symmetrical animals.

Question 6.
Find out the correct and wrong statement and find out the correct sequence
I. In the phylum cnidaria on the tentacles nematocysts are present.
II. In evolutionary history the annelid is the first segmented animal.
III. The roundworms are diploblastic bilateral animals.
IV. The arthropods excrete through flame cells.
a. I – False, II – False, III – True, IV – True
b. I – True, II – False, III – False, IV – True
c. I – True, II – True, III – False, IV – Flase
d. I – False, II – True, III – True, IV – False
Answer:
c. I – True, II – True, III – False, IV – False

Question 7.
Which of the following statements is correct?
(a) Polyp forms are free-living
(b) Medusa forms are sessile
(c) Medusa produces gametes
(d) Polyp reproduces sexually
Answer:
(c) Medusa produces gametes

Question 8.
What is the excretory organ of roundworm?
a. Flame cells
b. Rennet glands
c. Green glands
d. Malphigeal tubules
Answer:
b. Rennet glands

Question 9.
Sexual dimorphism is seen in
(a) Sycon
(b) Hydra
(c) Liver flukes
(d) Ascaris
Answer:
(d) Ascaris

Question 10.
Name the respiratory organ of Mollusca.
a. Ctenidia
b. Gills
c. Book lungs
d. Trachea
Answer:
a. Ctenidia

Question 11.
Name the excretory organ of Cephalo Chordata.
a. Mesonephridia
b. Metanephridia
c. Protonephridia
d. Flame cells
Answer:
d. Flame cells

Question 12.
Which of the following is the rasping organ of mollusks found in the mouth?
(a) radula
(b) pallium
(c) visceral mass
(d) mantle
Answer;
(a) radula

Question 13.
…………………….. are called as tunicates
a. Urochordates
b. Cephalo chordates
c. Vertebrata
d. Hemi Chordata
Answer:
a. Urochordates

Question 14.
The eggs of birds are ………………..
a. Megalecithal
b. Mesolecithal
c. Telolocithal
d. Alecithal
Answer:
a. Megalecithal

Question 15.
Urochordate means
(a) Chordates which have notochord in the head region
(b) Chordates which have notochord in the tail region of larval forms
(c) Chordates which have notochord in the tail region of adults
(d) Chordates which have no notochord
Answer:
(b) Chordates which have notochord in the tail region of larval forms.

Question 16.
Find out the correct pair.
a. Planula – Planeria
b. Regeneration – Annelida
c. Trochopore larva – Cnidaria
d. Veliger larva – Mollusca
Answer:
d. Veliger larva – Mollusca

Question 17.
Which one of the following is not correctly paired?
a) Ctenophora – Veliger
b) Annelida – Trochophore
c) Cnidaria – Planula
d) Porifera – Parenchymula
Answer:
a) Ctenophora – Veliger

Question 18.
Which of the following is the flight adaptation of birds?
(a) Pneumatic bones and strong flight muscles
(b) Homeothermic condition
(c) Migration to distant places
(d) Presence of homy covering on the beak
Answer:
(a) Pneumatic bones and strong flight muscles

(2 marks)

II. Very Short Questions

Question 1.
Distinguish invertebrates and chordates.
Answer:
Invertebrates:

• The major group of animals which do not have notochord or vertebral column are Invertebrates.
• These are lower animals.

Chordates:

• The major group of animals which have notochord or vertebral column are chordates.
• These are higher animals.

Question 2.
What are choanocytes?
Answer:
The inner layer of sponges is formed of flagellated collar cells called coanocytes. They maintain water flow through the sponges thus facilitating respiratory and digestive functions.

Question 3.
What are choanocytes?
Answer:
The inner layer of sponges has a special type of cells called choanocytes. These flagellated collar cells create and maintain water flow through the sponge. It helps in respiration and digestion.

Question 4.
Define organ? Which was the first animal to have an organ system?
Answer:

• Different kinds of tissues aggregate to form an organ to perform a specific function.
• In phylum Platyhelminthes, the organ level of organisation is first formed.

Question 5.
Differentiate between a complete digestive system from an incomplete digestive system.
Answer:

Incomplete Digestive System	Complete Digestive System
1. There is a single opening in the digestive system which serves as both mouth and anus. (Eg.) Platyhelminthes	1. There are separate openings for the mouth and anus. (Eg.) Chordates

Question 6.
What are asymmetrical animals?
Answer:
The animals which lack a definite body plan and any plane passing through the center of the body does not divide them into two equal halves are known as asymmetrical animals, e.g. Sponges.

Question 7.
What is radial symmetry?
Answer:
When any plane passing through the central axis of the body divides an organism into two identical parts, it is called radial symmetry, e.g. Cnidarian.

Question 8.
What is bilateral symmetry?
Answer:
The symmetry in which the animals have two similar halves on either side of the central place is bilateral symmetry, e.g. Flatworms and annelids.

Question 9.
What are deutrostomia ?
Answer:
Eumetazoans in which the anus is formed from or near the blastopore and the mouth is formed away from the blastopore are deuterostomes.

Question 10.
What are the advantages of bilaterally symmetrical animals?
Answer:
The bilaterally symmetrical animals can seek food, locate mates, escape from predators and move more efficiently. These animals have dorsal-ventral sides and anterior, posterior ends, right and left sides. They exhibit cephalization with sense organs and brain at the anterior end of the animal.

Question 11.
Differentiate the respiratory pigment haemoglobin from haemocyanin.
Answer:

Haemoglobin	Haemocyanin
1. It’s an iron-containing respiratory pigment.	It’s a copper-containing respiratory pigment.
2. This is present in Annelida and Chordata	This is present in molluscan blood.

Question 12.
What are pseudocoelomates?
Answer:
The animals which have a body cavity that is not fully lined by the mesodermal epithelium are called pseudocoelomates. The pseudocoel is filled with pseudocoelomic fluid. It acts as a hydrostatic skeleton and allows free movement of visceral organs and circulation of nutrients e.g. Roundworms.

Question 13.
What is cleidoic egg?
Answer:
If the female organisms lay cleidoic eggs or shelled egg then it is known as cleidoic eggs.

Question 14.
What are the extraembryonic membranes present in reptiles?
Answer:

1. Amnion
2. Allantois
3. Chorion
4. Yolk sac

Question 15.
Distinguish between schizocoelomates and enterocoelomates
Answer:
Schizocoelomates:
In schizocoelometes, the body cavity is formed by splitting mesoderm, e.g. Annelids, arthropods, and mollusks.

Enterocoelomates:
In enterocoelomates, the body cavity is formed from the mesodermal pouches of the archenteron. e.g. Echinoderms, hemichordates and chordates.

(3 marks)

III. Short Questions

Question 1.
What are the structures formed from ectoderm endoderm and mesoderm?
Answer:

1. Ectoderm – Skin, Hair, Nerves, Nail, Teeth
2. Mesoderm – Muscles, Bones, Heart
3. Endoderm – Intestine, Lungs, Liver.

Question 2.
Name the parts A, B, and C in the diagram?
Answer:

A) Ectoderm
B) Pseudo coelom
c) Mesodorm

Question 3.
Differentiate parazoa from eumetazoa?
Answer:

Parazoa	Eumetazoa
1.Multicellular	Multicellular
2. Cells are loosely	Well-developed tissues arranged. and organ system is present

Question 4.
Match


a) I – b, II – d, III – a, IV – c
b) I – a, II – b, III – d, IV – c
c) I – b, II – a, III – d, IV – c
Answer:
a) I – b, II – d, III – a, IV – c

Question 5.
Distinguish between Agnatha and Gnathostomata.
Answer:
Agnatha:

• These include jawless fish-like aquatic vertebrates.
• They do not have paired appendages.

Gnathostomata:

• These include jawed vertebrates.
• They have paired appendages.

Question 6.
In the given diagram Balanoglossus mark A, B, and C.

Answer:
A) Proboscis
B) Collarette
c) Genital wings

Question 7.
Explain various patterns of organisation in animals.
Answer:
Animals exhibit different patterns of organisation:
The cellular level of organisation:

• Cells are loosely arranged without the formation of tissues.
• There is a division of labour among the cells, e.g., sponges.

Tissue level of organisation:

• Cells which perform a similar function are grouped into tissues.
• The tissues perform a common function, e.g., cnidarians.

Organ level of organisation:
Different kinds of tissues aggregate to form an organ to perform a specific function e.g., flatworms and other hyper phyla.

Organ system level of organisation :

• The tissues are organized to form organs and organ systems.
• All the organ systems function in a coordinated manner.

Question 8.
Look at the picture given below and answer questions.
a) What is the name of this fish?
b) What is the name of the larva of this fish?
c) What is the shape of the mouth?

Answer:
a) iprey
b) Ammocete
c) Circular

Question 9.
Classify animals based on coelom.
Answer:
The cavity between the body wall and the gut wall is called coelom. If the animals do not have coelom, they are called acoelomates. e.g., flatworms. In some animals, the body cavity is not fully lined by the mesodermal epithelium. The mesoderm is formed as scattered pouches between the ectoderm and endoderm. Such a body cavity is called a pseudocoel. The animals which have pseudocoel e.g. roundworms.

If the coelom develops within the mesoderm and is lined by mesodermal epithelium it is called eucoelom. The animals which have true coelom are called eucoelomates. If the body cavity is formed by splitting of mesoderm, the animals are called schizocoelomates e.g., Annelids, arthropods and mollusks. If the body cavity is formed from the mesodermal ‘ pouches of archenteron, the animals are called enterocoelomate animals, e.g., echinoderms, hemichordates and chordates.

(5 Marks)

IV. Essay Questions

Question 1.
Explain various patterns of organisation in animals.
Answer:
Animals exhibit different patterns of organisation:
The cellular level of organisation:

• Cells are loosely arranged without the formation of tissues.
• There is a division of labour among the cells, e.g., sponges.

Tissue level of organisation:

• Cells which perform a similar function are grouped into tissues.
• The tissues perform a common function, e.g., cnidarians.

Organ level of organisation:
Different kinds of tissues aggregate to form an organ to perform a specific function e.g., flatworms and other hyper phyla.

Organ system level of organisation:

• The tissues are organised to form organs and organ systems.
• All the organ system function in a coordinated manner.

Question 2.
Write the general characters of the phylum Ctenophora.
Answer:

• The animals are marine, diploblastic and radially symmetrical.
• They have eight external rows of ciliated comb plates which help in locomotion.
• Bioluminescence is seen.
• They lack nematocysts but have lasso cells which help in food capture.
• Digestion is by both extracellular and intracellular.
• Sexual reproduction is seen.
• Fertilization is external and development is indirect.
• Cydippid larva is seen, e.g., Pleurobrachia.

Question 3.
Compare Platyhelminthes with Aschelminthes?
Answer:

Platyhelminthes	Aschelminthes
1. The body is flattened one	They are round in shape.
2. They are bilateral and triploblastic animal.	They are bilateral and triploblastic animal.
3. Acoelomate	Pseudo coelom is present.
4. They have pseudo segmentation	The body is unsegmented
5. Excretion is through flame cells.	Excretion is through rennet glands.
6. Sexes are not separate. They are monoecious.	Sexes are separate and exhibit sexual dimorphism.
7. Some show regeneration capacity.	No regeneration capacity.
8. Larva is present.	No larva
9. (Eg.) Tape worm, Planeria	(Eg.) Ascaris

Question 4.
Write the general characters of the phylum Mollusca.
Answer:

• Molluscs are terrestrial or aquatic with organ system level of organisation.
• They are triploblastic, bilaterally symmetrical, coelomate animals.
• Body is divided into head, foot and visceral hump.
• The digestive system is complete.
• Nephridia are the excretory organs.
• Open type of circulatory system is seen.
• Blood contains a copper-containing respiratory pigment called hemocyanin.
• They are oviparous.
• Development is indirect with a veliger larva, e.g., Pila and Octopus.

Question 5.
What are the characteristic features of Hemichordata?

• They possess the characters of invertebrates and chordates.
• This phylum consists of soft worm-like organisms.
• They are triploblastic coelomate animals.
• They are bilaterally symmetrical.
• Their circulatory system is simple and open type.
• They are ciliary feeders.
• Respiration is through paired gill silts opening into the pharynx.
• Excretion is through the glomerulus.
• The nervous system is primitive sexes are separate.
• In its development, there is a free-swimming to maria larva.

Question 6.
Write the general characters of hemichordate.
Answer:

• The Hemichordates have both invertebrate and vertebrate characters.
• They are worm-like, tuberculous animals.
• They are bilaterally symmetrical, triploblastic coelomate animals with organ system level of organisation.
• The body is divided into proboscis, collar, and trunk.
• They are ciliary feeders.
• The circulatory system is simple and open.
• Excretion is by a single proboscis gland or glomerulus situated in the proboscis.
• Sexes are separate.
• Fertilization is external.
• Development is indirect with tomaria larva, e.g., Balanoglossus.

Question 7.
Write the general characters of cephalochordates.
Answer:

• They are marine found in shallow waters.
• They lead a burrowing mode of life.
• They are fish-like with notochord, nerve cord and pharyngeal gill slits throughout their life.
• Closed type of circulatory system is seen without heart.
• Excretion is by protonephridia.
• Sexes are separate.
• Fertilization is external.
• Development is indirect with a larva e.g. Amphioxus.

Question 8.
What are the general characters of mammals?
Answer:

• The body is covered by hairs.
• They are found in a variety of habitats.
• The presence of the mammary gland is the most unique feature of mammals.
• They have two pairs of limbs.
• The skin consists of sweat glands and sebaceous glands.
• Exo skeleton includes horns spines, scales claws, etc.
• Teeth are thecodont heterodont and diphyodont.
• The heart is four-chambered and posses a left systematic arch.
• Mammals have a large brain when compared to other animals.
• Their kidneys are metanephric and are ureotelic.
• All are homeothermic.

Question 9.
Give three distinct features of all chordates that are seen at some stage of their life cycle? What is the fate of two characters out of three in the matured adults?
Answer:

1. Presence of notochord below the nerve chord and above the alimentary canal.
2. The presence of the nerve cord lies above the notochord and below the dorsal body wall.
3. Presence of pharyngeal gill slits in all chordates at some stage of their life cycle.

Features saw in the matured adult animals

Larva	Adult
Notochord	It may be partially or completely replaced by a backbone.
Nerve cord	They enlarged to form the brain and spinal cord.

Question 10.
Compare the chordates with non-chordates?
Answer:

Chordates	Non-chordates
1. Notochord is present	Absence of notochord.
2. Dorsal hollow and single nerve cord	Double ventral solid nerve cord.
3. Pharynx perforated by gill slits.	Gill slits absent.
4. Heart is ventrally placed.	Heart indoors or laterally placed or absent.
5. A post-anal tail is present	Post anal tail is absent
6. Alimentary canal placed ventral to the nerve cord	The alimentary canal is placed dorsal to the nerve cord.

Question 11.
What are the parts of ABCD in the model diagram of Chordata?

Answer:
A) Dorsal Nerve Cord
B) Notochord
C) Mouth
D) Pharyngeal gill clefts
E) Muscle segment

Question 12.
Look into the given diagram and answer the question.
a) What is the name of the organism.
b) What is the respiratory organ of this animal.
c) What type of metamorphosis is seen?
d) Whether this organism contain nerve card?
e) What is the outer covering of it’s body?

Answer:
a) Ascidian
b) Gill clefts
c) Retrogressive metamorphosis
d) The larva consists of a nerve cord.
e) Tunic