Question 1

Which one of the following group of animals is bilaterally symmetrical and triploblastic?

Accepted Answer

Animal are classified on the basis of symmetry of body plan and germ layers if the body plan is made up of three germ layers called as triploblastic and if it made up of two germ layers called as diploblastic. Ctenophores are biradially symmetrical and diploblastic, whereas some species are triploblastic. Sponges are asymmetrical and and diploblastic. Coelenterates are radially symmetrical and diploblastic. Aschelminthes are bilaterally symmetrical and triploblastic. Thus, the correct answer is option D.

Question 2

The excretory organs of flatworms (Platyhelminthes) are

Accepted Answer

The excretory organs of flatworms (Platyhelminthes) are flame cells and function like a kidney, removing waste materials.Nephridia remove metabolic wastes from an animal's body. They are present in annelids.The Malpighian tubule is a tubular excretory organ, a number of which open into the gut in insects and some other arthropods.Nematodes have a unique excretory system consisting, in simpler species, of one or two one-celled glands called renette cells. Thus, the correct answer is option A.

Question 3

Flame cells/solenocytes are main excretory structures of

Accepted Answer

A flame cell is a specialized excretory cell found in the simplest freshwater invertebrates, including Platyhelminthes. Flame cells function like a kidney and remove waste materials. Bundles of flame cells are called protonephridia. Flame cells function on the basis of filtration & resorption. So, option B is correct.

Question 4

Mesoderm is present as scattered pouches in between the ectoderm and endoderm in

Accepted Answer

Mesoderm is a layer of the germ layer which is present between ectoderm and endoderm and arises during gastrulation. Mesoderm gives rise to bones, muscles, circulatory system, heart and internal sex organs. Mesoderms present in scattered pouches in between ectoderm and endoderm is found in Aschelminthes.So, the correct option is 'Aschelminthes'

Question 5

Flame cells of flatworms help in(i) Osmoregulation(ii) Digestion(iii) Reproduction(iv) Excretion(v) Bioluminescence

Accepted Answer

A flame cell is a specialized excretory cell found in the simplest freshwater invertebrates such as flatworms. Flame cells function like a kidney and removes waste materials. Bundles of flame cells are called protonephridia. The function of these cells is to regulate the osmotic pressure and maintains ionic balance.

Question 6

Flame cells are excretory organ of

Accepted Answer

Flame cells are excretory organs in animals belonging to the phylum Platyhelminthes. Of the animals given as options, only Planaria belongs to the phylum Platyhelminthes. So, the correct answer is 'Planaria'.

Question 7

Which of the following is pseudocoelomate?

Accepted Answer

Leech is an Annelid and has a well-developed coelom. Liver fluke is a Platyhelminthes and is the acoelomate animal. Hookworm is Ancylostoma, it is an Aschelminthes animal and is pseudocoelomate as their body cavity is pseudocoelom (fluid filled body cavity present in between the mesoderm and ectoderm). Jellyfish is a Coelenterate animal and is acoelomate. Thus, the correct answer is option C.

Question 8

The greatest ability of regeneration amongst the animals is found in

Accepted Answer

Regeneration is the capability of developing into a whole organism from a part of the body. Regeneration is well marked in the organisms of phylum Platyhelminthes, like Planaria. Ascaris belongs to phylum Nematoda and Pheretima and Hirudinia belong to phylum Annelida. Planarians are non-parasitic flatworms. All their tissues, irrespective of from where the tissue was derived (from endoderm, mesoderm or ectoderm) display remarkable regenerative capacities. So, the correct answer is 'Planaria (Dugesia)'.

Question 9

Animal of which phylum have hooks and suckers and are endoparasite on other animals?

Accepted Answer

Platyhelminthes or flatworms are dorsoventrally flattened and bilaterally symmetrical worms. They are endoparasites and have parasitic adaptations like hooks and suckers.So the correct option is A.

Question 10

Which one of the following statement about given animals is correct?

Accepted Answer

Flatworms (Platyhelminthes) are acoelomates i.e. they lack a coelom. Molluscs and insects (Arthropoda) are coelomates as they have a true coelom derived from the germ layer mesoderm. Roundworms (Aschelminthes) are pseudocoelomates as the coelom is not derived from the mesoderm. Thus, the correct answer is option B.

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Phylum Aschelminthes

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Phylum Platyhelminthes

Aschelminthes