Classification of Animals Test - 5

Sponges do not have a digestive system. Hence they don't have a mouth and anus. The functions of digestive system are performed by canal system.

Coelenterates have a mouth andanus as they have a gastrovascular cavity. 

Phylum Platyhelminthes has incomplete digestive tract but mouth and anus are present.

Phylum Nemathelminthes has a completeand digestive tract with mouth and anus.

So, the correct answer is'Sponges'.

Ascarias is is an intestinal infection that occurswhen the eggs of a parasitic roundworm, Ascaris lumbricoides areingested. There is an increase in the number of WBCs in the body i.e.,leucocytosis and decrease in the number of eosinophils (eosinophilia) can beobserved. There is a very high fever, restlessness, disturbed sleep, abdominalpain and extensive haemorrhage and inflammation of pancreas can be observed.

Porifera is multicellular organisms, which are sedentary in nature. Most of them are marine.
The body wall is diploblastic, which consists of an outer layer, called aspinacoderm and an inner layer, called as choanoderm.
The canal system mainly comprises of incurrent and excurrent canals, which arelined with pinacocytes and radial canals, which are lined with choanocytes(flagellated cells).
The body walls contain numerous pores, called as Ostia through which waterenters the body through a canal system into the central body cavity called asthe spongocoel.
Sponges have an exoskeleton, which is made up of either spongin fibers orcalcareous/siliceous spicules or a combination of both.

So, the correct answer is option B.

A. Planktonic organisms are the ones that float on thesurface of sea water.

B. Nectonic organisms are the ones that swim in the seawater.

C. Neuston organisms are the ones that move on the surfacefilm of the water.

D. Sedentary organisms are the ones that are fixed at aplace i.e. they are attached to a substratum.

Sponges are sessile organisms as they are attached to asubstratum. Hence, they are sedentary organisms.

So, the correct answer is 'Sedentary'.

Taenia and Fasciola are parasiticPlatyhelminthes. Pheretima isan annelid animal. Planaria isa nonparasitic or free-living platyhelminth. Planaria (Dugesia) belong to class Turbellaria ofphylum Platyhelminthes. Mostly free-living flatworms are placed inclass Turbellaria

So, the correct answer is 'Planaria'

Internalfertilization is the fusion of an egg cell with a sperm during sexualreproduction inside the body of a parent. For this to happen there needs to bea method for the male to introduce the sperm into the female's reproductivetract. The same kind of fertilization occurs in Dugesia, Fasciola and Schistosoma. Internalfertilization is one of the main characteristics of platyhelminthes.

The animal phyla Porifera is considered as side line to the major trendsof evolution. Porifera have cellular level organisation and theirindividual cells functioning independently, they lack the coordinated patterns of cell functions seen in more specialized tissues or organs of other animal phyla. Thus, the correct answer is option A.

Bilaterallysymmetrical means left and right halves of the body has thesame design. Dorsiventrally flattened means the front and back of the organism are flat. These two features are present in the organisms belonging to group Platyhelminthes. Liver fluke is one of the examples of group Platyhelminthes. It possesses both features. Hence, the correct answer isoption A. 

Planarian belongs to classTurbellaria (phylum Platyhelminthes). It is free living. These are flatwormsthat have a bilaterally symmetrical body. These are acoelomate.

So, the correct answer is optionB.

Classification of animals is based on the level of organization asdiploblastic or triploblastic based on cellular, tissue, organ, organsystem etc on the basis of which the animals are classified under thedifferent phyla. At a very basic level of classification,true animals can be largely divided into threegroups based on the type of symmetry of their body plan:radially symmetrical, bilaterally symmetrical, and asymmetrical. On the basisof the Body Cavity or Coelom which is the space between the body walland the alimentary canal, which is produced by splitting of mesoderm, duringembryonic development. On the basis of nature ofthe coelom, animals are classified into three types.There is no classification on the basis of the nervous system.

So, the correct optionis 'presence or absence of a nervous system'.

A whipworm infection, also known as trichuriasis, is an infection of thelarge intestine caused by a parasite called Trichuris trichiura. Mild whipworminfections often cause no symptoms. Abdominal pain, loss of appetite, anddiarrhea occur when a large number of worms are present in the colon. Weightloss, bleeding from the intestine, and anemia may result, especially inchildren with heavy infections. Occasionally, a massive infection causes therectum to protrude through the anus (rectal prolapse).

So, the correct answeris 'All of the above'.

Euglena is a genus ofunicellular flagellated Protists.

Penicillium is agenus of Ascomycetes (fungi).

Hydra is agenus of small, simple, radially symmetrical fresh-wateranimals belonging to the phylum Cnidaria.

Spongilla is agenus of freshwater sponges in the family Spongillidae found in lakesand slow streams.

Sponges belongto the phylum Porifera and are sessile metazoans. They aremulticellular but have unspecialized cells that can transform into othertypes and that often migrate between the main cell layers and the mesophyll inthe process. 

Platyhelminthesvery commonly known as flatworms or tapeworms, these animals are soft-bodiedinvertebrate animals. There are around 20,000 species of these animals. A fewof these live as parasites on humans and other animals.

Flatworms reproduce asexually byfragmentation . They don't required water 

 Platyhelminthes arehermaphrodites so they can produce eggs as well as sperm for fertilization 

Another method of sexualreproduction is absorption of sperm from the body surface into the skin viaphysical contact. So fertilization occurs in female genital tract 

So the correct answer is ' femalegenital tract'.

The oviducts (fallopian tubes), uterus and vagina constitute the female accessory ducts. Each fallopian tube is about 10-12 cm long and extends from the periphery of each ovary to the uterus, the part closer to the ovary is the funnel-shaped infundibulum. The edges of the infundibulum possess finger-like projections called as fimbriae, which help in the collection of the ovum after ovulation. The infundibulum leads to a wider part of the oviduct called as ampulla. The last part of the oviduct, the isthmus has a narrow lumen and it joins the uterus. The ostium of the fallopian tube (plural ostia) may refer to the proximal or distal opening of the tube.

The proximal tubal opening (ostium) is located within the uterus at the utero-tubal junction and accessible via hysteroscopy. The distal tubal opening (or abdominal ostium) is the opening in the infundibulum of the uterine tube into the abdominal cavity.

Therefore, the correct answer is option B.