Question No : 43
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.
Question No : 44
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.
Question No : 45
Which of the following statement(s) is/are correct regarding phylum aschelminthes?
(i) The body is circular in cross-section hence the name roundworms.
(ii) Alimentary canal is complete with a well-developed muscular pharynx.
(iii) Sexes are separate (dioecious), i.e., males and females are distinct.
(iv) Nephridia help in osmoregulation and excretion.
Question No : 46
Which of the following statement(s) is/are correct regarding phylum mollusca?
Question No : 47
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.
Question No : 48
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.
Question No : 49
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.