Which of the following character is absent in all chordates?
Diaphragm
Coelom
Pharyngeal gill clefts
Dorsal nerve cord
Correct Answer :
A. Diaphragm
Diaphragm is a membrane that separates thoracic cavity from abdominal cavity. It is present only in mammals. All other chordates do not have diaphragm as their body cavity is not divided into thoracic and abdominal cavities.
Related Questions
The following statement are associated with the occurrence of notochord. Identify the incorrect statement.
It is present only in larval tail in ascidians.
It is replaced by a vertebral column in adult frog.
It is absent throughout the life in humans from the very beginning.
It is present throughout life in Amphioxus.
Which of the follwoing statement(s) is/are correct?
(i) Organ systems in different group of animals show various patterns of complexities.
(ii) The digestive system in platyhelminthes has only a single opening to the outside of the body that serve as both mouth and anus, and is hence called complete.
(iii) In open type of circulatory system, the blood is pumped out of the heart and the cells and tissues are directly bathed in it.
(iv) In closed type, the blood is circulated through a series of vessels of varying diameters (arteries, veins and capillaries).
Only (i)
Both (ii) and (iii)
(i), (iii) and (iv)
All of these
Match the phylum given in column - I with their example given in column - II and choose the correct option.
| Column -I | Column- II |
|---|---|
| (Phylum) | (Examples) |
| A. Echinodermata | I. Ascidia, Doliolum |
| B. Hemichordata | II. Asterias, Ophiura |
| C. Urochordata | III. Branchiostoma |
| D. Cephalochordata | IV. Balanoglossus, Saccoglossus |
A IV; B II; C I; D III
A II; B IV; C I; D III
A II; B IV; C III; D I
A II; B I; C IV; D III
Which of the following statements is incorrect ?
Prawn has two pairs of antennae.
Nematocysts are characteristic feature of the phylum cnidaria.
Millipedes have two pairs of appendages in each segment of the body.
Animals that belong to phylum porifera are exclusively marine.
In which of the phylum, excretory organ like proboscis gland is present?
Hemichordata
Chordata
Echinodermata
Annelida
Which of the following animal's body is covered by calcareous shell and unsegmented with a distinct head, muscular foot, and visceral hump?
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Which of the following character is absent in all chordates?
Diaphragm
Coelom
Pharyngeal gill clefts
Dorsal nerve cord
The figure given below shows the germinal layers marked as A, B, C and D. Identify the label showing undifferentiated layer and its location?
A, Between B & C
B, Between A & C
C, Between C & D
D, Between A & B
Read the following statements and answer the question.
(i) They are exclusively marine, radially symmetrical, diploblastic organisms with tissue level of organisation.
(ii) Body bears eight external rows of ciliated comb plates, which help in locomotion.
(iii) Digestion is both extracellular and intracellular.
(iv) Reproduction takes place only by sexual means.
Which of the following phylum is being described by above statements?
Platyhelminthes
Arthropoda
Mollusca
Ctenophora
Examine the figures A, B and C. In which one of the four options all the items A, B and C are correctly identified ?
A - Sycon, B - Euspongia, C - Spongilla
A - Euspongia, B - Spongilla, C - Sycon
A - Spongilla, B - Sycon, C - Euspongia
A - Euspongia, B - Sycon, C - Spongilla
Which of the following statements (i - v) are correct ?
(i) The pelvic fins of female sharks bear claspers.
(ii) In Obelia, polyps produce medusae sexually and medusae form the polyps asexually.
(iii) Flame cells in platyhelminthes help in osmoregulation and excretion.
(iv) In non-chordates, central nervous system is ventral, solid and double.
(v) Pinnae are present in mammals.
(ii), (iv) and (v)
(i), (iii) and (v)
(iii), (iv) and (v)
(i), (ii) and (iii)
Match the characteristic feature/terms given in column I with the phylum to which they belongs given in column II and choose the correct option.
| Column-I | Column-II |
|---|---|
| (Characteristic feature/term) | (Phylum) |
| A. Choanocytes | I. Platyhelminthes |
| B. Cnidoblasts | II. Ctenophora |
| C. Flame cells | III. Porifera |
| D. Nephridia | IV. Coelenterata |
| E. Comb plates | V. Annelida |
A II; B I; C IV; D V; E III
A II; B IV; C I; D V; E III
A V; B I; C III; D II; E IV
A III; B IV; C I; D V; E II
Refer the following statement and answer the question. 'Name of X is derived from stinging capsules. It exhibits metagenesis containing two body forms in which sessile and cylindrical form is called Y and umbrella shaped and free swimming is called Z. Identify X, Y, and Z.
X - Coelenterate, Y - Polyp, Z - Medusa
X - Cnidarian, Y - Medusa, Z - Polyp
X - Ctenophora, Y - Radula, Z - Hypostome
X - Porifera, Y - Osculum, Z - Radula
In amphibians, respiration occurs through
gills
lungs
skin
all of these
Which of the following class is being correctly described by given statements (i - iv)?
(i) All living members of this class are ectoparasites on some fishes.
(ii) They have a sucking and circular mouth without jaws.
(iii) Circulation is of closed type.
(iv) They are marine but migrate for spawning to fresh water. After spawing, within a few days they die.
Cyclostomata
Chondrichthyes
Osteichthyes
Amphibia
Which one of the following features is common in silverfish, scorpion, dragonfly and prawn?
Three pairs of legs and segmented body.
Chitinous cuticle and two pairs of antennae.
Jointed appendages and chitinous exoskeleton.
Cephalothorax and tracheae.
Which of the following possesses poison sting and belongs to class chondrichthyes?
Labeo
Myxine
Clarias
Trygon
Which of the following is not a chordate character?
Presence of paired pharyngeal gill slits
Ventral heart
Solid and ventral nerve cord
Presence of post-anal tail
Which of the following is a fresh water sponge?
Sycon
Euspongia
Spongilla
Pleurobrachia
Identify the figures A, B and C and choose the correct option.
A - Male Ascaris, B - Hirudinaria (leech), C- Nereis
A - Female Ascaris, B - Nereis, C-Hirudinaria (leech)
A - Female Ascaris B- Hirudinaria (leech), C - Nereis
A - Male Ascaris, B - Nereis, C- Hirudinaria (leech)
In amphibians, heart is ________ chambered.
two
three
four
none of these
Which of the following statement(s) is/are correct regarding phylum coelenterata?
(i) They are aquatic, mostly marine, sessile or freeswimming, radially symmetrical animals.
(ii) They have a central gastro-vascular cavity with a single opening called hypostome.
(iii) Digestion is extracellular and intracellular.
(iv) Examples are Sycon, Spongilla and Euspongia.
(i) and (ii)
(i) and (iv)
(i), (ii) and (iii)
All of these
Tracheae of cockroach and mammal are similar in having
paired nature.
non-collapsible walls.
ciliated inner lining.
origin from head.
Which of the following phylum is being described by the given statements?
(i) These are primitive multicellular animals and have cellular level of organization.
(ii) Digestion is intracellular.
(iii) They have a water transport or canal system.
(iv) They reproduce asexually by fragmentation and sexually by formation of gametes.
Porifera
Ctenophora
Coelenterata
Platyhelminthes
Which of the following statement(s) is/are correct?
(i) Animals in which the cells are arranged in two embryonic layers, an external ectoderm and an internal endoderm, are called diploblastic animals.
(ii) Notochord is an ectodermally derived rod like structure formed on the ventral side during embryonic development in some animals.
(iii) In some animals, the body cavity is not lined by mesoderm, instead, the mesoderm is present as scattered pouches in between the ectoderm and endoderm and such a body cavity is called pseudocoelom.
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All of these
In phylum arthropoda, excretion takes place through
nephridia
flame cells
malphigian tubules
gills
Which of the following is not a characteristic of phylum echinodermata ?
They have a water vascular system.
They have an internal skeleton.
They are protostomes.
They have bilateral symmetry at larval stage.
Column-I contains organisms and column-II contains their exeretory structures. Choose the correct match form the options given below.
| Column- I | Column -II |
|---|---|
| (Organism) | (Excretory structures) |
| A. Cockroach | I. Nephridia |
| B. Cat fish | II. Malpighian tubules |
| C. Earthworm | III. Kidneys |
| D. Balanoglossus | IV. Flame cells |
| E. Flatworm | V. Proboscis gland |
A I; B III; C II; D IV; E V
A III; B I; C II; D V; E IV
A II; B I; C III; D V; E IV
A II; B III; C I; D V; E IV
Hemichordates have now been placed with the nonchordates, close to echinoderms, because true
notochord is absent.
pharyngeal gill-slits are lacking.
dorsal nerve cord is absent.
heart is lacking.
Which of the following is a chordate feature and not shared by the non-chordates ?
Metamerism
Axial organization
Bilateral symmetry
Pharyngeal gill slits