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.
Correct Answer :
C. It is absent throughout the life in humans from the very beginning.
Notochord is a flexible rod like structure that forms the main support of the body in the lowest chordates. It is not absent in humans throughout their life. Notochord is present in embryonic stage and get changed or replaced by vertebral column in the adult.
Related Questions
Which of the following is a connecting link between invertebrates and non-invertebrates?
Sphenodon
Balanoglossus
Tadpole larva
Crocodile
Which of the following pairs of animals comprises jawless fishes?
Mackerals and rohu
Lampreys and hag fishes
Guppies and hag fishes
Lampreys and eels
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
Which of the following statement is incorrect?
Platyhelminthes has incomplete digestive system.
In coelenterates, the arrangement of cells is more complex.
Nereis is monoecious but earthworms and leeches are dioecious.
Simple and compound eyes are present in the animals of those phylum whose over two-thirds of all named species on earth are arthropods.
Which of the following phylum is being described by the given statements?
(i) They are bilaterally symmetrical,triploblastic, segmented and coelomate animals.
(ii) The body consists of head, thorax, abdomen and have jointed appendages.
(iii) Circulatory system is of open type.
(iv) Excretion takes place through malphigian tubules.
Arthropoda
Annelida
Mollusca
Echinodermata
Refer the following animals and identify those which have a fluid filled body cavity with a complete lining derived from mesoderm.
(i) Sycon (ii) Butterfly
(iii) Nereis (iv) Sea fan
(v) Scorpion (vi) Pila
(i) and (iii) only
(ii) and (iv) only
(ii), (iii), (v) and (vi) only
All of these
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 is an incorrect statement regarding flatworms ?
They are acoelomates.
They are bilaterally symmetrical.
They lack a digestive system.
They have a circulatory system.
Which one of the following groups of animals is correctly matched with its characteristic feature without even a single exception ?
Reptilia : possess 3 - chambered heart with one incompletely divided ventricle.
Chordata : Possess a mouth provided with an upper and lower jaw.
Chondrichthyes : Possess cartilaginous endoskeleton.
Mammalia : Give birth to young one.
Which of the following class is being described by the given statements (i - iv)?
(i) They are found in a variety of habitats- polar ice-caps, deserts, mountains, forests, grasslands and dark caves.
(ii) Most unique mammalian characteristic is the presence of mammary glands by which the young ones are nourished.
(iii) Heart is four-chambered.
(iv) Sexes are separate and fertilization is internal.
Reptilia
Aves
Mammalia
Amphibia
Which of the following feature in birds indicates their reptilian ancestory ?
Eggs with a calcareous shell
Scales on their hind limbs
Four-chambered heart
Two special chambers-crop and gizzard in their digestive tract
Identify the correct characteristics of porifera.
- Commonly known as sea walnuts.
- Presence of ostia and collar cells.
- Exhibit tissue level of characteristics.
- It is the largest phylum of animal kingdom.
- The body is supported by spicules and sponging fibers.
- Contains cnidocytes which is used for defense, anchorage and capturing of prey.
(ii), (v) only
(i), (ii), (vi) only
(i), (ii), (iii), (iv) only
All of these.
Identify the figure with its correct name and phylum.
Sycon - Porifera
Aurelia - Coelenterata
Pleurobrachia - Ctenophora
Tapeworm - Platyhelminthes
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
Heart is three - chambered in reptiles, except
turtle
Chameleon
Naja (Cobra)
crocodile
Column I contains zoological names of animals and column II contains their common name. Match the following and choose the correct option.
| Column -I | Column- II |
|---|---|
| A. Physalia | I. Sea anemone |
| B. Meandrina | II. Brain coral |
| C. Gorgonia | III. Sea fan |
| D. Adamsia | IV. Portuguese man-of-war |
A III; B II; C I; D IV
A IV; B III; C II; D I
A IV; B II; C III; D I
A II; B III; C I; D IV
Which of the following animal's body is covered by calcareous shell and unsegmented with a distinct head, muscular foot, and visceral hump?
Click to check answer
Click to check answer
Click to check answer
Click to check answer
Which of the following group of animals belongs to the same phylum?
Earthworm, pinworm, tapeworm
Prawn, scorpion, Locusta
Sponge, Sea anemone, starfish
Malarial parasite, Amoeba, mosquito
The figure given below is the characteristic structure of the phylum in which animals are aquatic, free swimming or sessile, mostly marine, radially symmetrical. Identify the phylum and correct function of the structure.
Ctenophora; Emission of light.
Porifera; Feeding, respiration and excretion.
Cnidarian; Anchorage, Defense and food capturing
Mollusca; Locomotion, transport of food and respiration.
Which of the following statement(s) is/are correct regarding class aves?
(i) The forelimbs are modified into wings and the hindlimbs generally have scales and are modified for walking, swimming or clasping the tree branches.
(ii) Heart is completely four-chambered.
(iii) They are warm- blooded (homoiothermous) animals i.e., they are able to maintain a constant body temperature.
(iv) They are oviparous and development is direct.
Both (i) and (iii)
Both (i) and (iv)
(i), (ii) and (iii)
All of these
Refer the figures A, B, C and D given below. Which of the following options shows the correct name of the animals shown by the figures A, B, C and D ?
A – Locust, B – Scorpion, C – Prawn, D – Pila
A – Locust, B – Prawn, C – Scorpion, D – Pila
A – Locust, B – Scorpion, C – Prawn, D – Snail
A – Butterfly, B – Scorpion, C – Prawn, D – Pila
Refer the types of cells present in some animals. Each cell is specialized to perform a single specific function except
Cnidocytes
Choanocytes
Interstitial cells
Gastrodermal cells
In ctenophora, the body bears _______ external rows of ciliated comb plates, which help in locomotion.
five
six
seven
eight
Which of the following possesses electric organs and belongs to class chondrichthyes?
Torpedo
Petromyzon
Trygon
Exocoetus
Which of the following statement(s) is/are correct for class amphibia?
(i) Body is divisible into head and trunk.
(ii) Respiration is through gills only.
(iii) The heart is two chambered i.e. one auricle and one ventricle.
(iv) Fertilization is internal.
Only (i)
Only (iv)
(i), (ii) and (iii)
All of these
Which of the following is a correct match of a phylum with their three examples?
PlatyhelminthesPlanaria, Schistosoma, Enterobius
Mollusca Loligo, Sepia, Octopus
Porifera Spongilla, Euplectella, Pennatula
Cnidaria Bonellia, Physalia, Aurelia
Few cnidarians like corals have a skeleton composed of
calcium hydroxide
calcium sulphate
calcium carbonate
sodium bicarbonate
The given figure shows some characteristic features marked as chordates. Identify the correct labelling A,B,C and D.
A-Notochord; B-Post-anal part; C-Gill slits; D-Nerve cord
A-Nerve cord; B-Notochord; C-Post-anal part; D-Gill slits
A-Notochord; B-Nerve cord; C-Gill slits; D-Post-anal part
A-Gill slits; B-Post-anal part; C-Nerve cord; D-Notochord
Which of the following statements (i – v) are incorrect ?
- Circulatory system in arthropods is of closed type.
- Parapodia in annelids helps in swimming.
- Phylum mollusca is the second largest animal phylum.
- Aschelminthes are dioecious.
(i) only
(iii) only
(i) and (iii)
(iii) and (iv)