Phylum protozoa, characteristic of protozoa, 26 MCQ of Protozoa, bsc sem-1 zoology objective question,

 Phylum Protozoa 

The Protozoa are heterogeneous assemblage of some 50,000 cellular or single- cell organism. 

found worldwide in most habitats. Protozoa means ‘first animal’ the simplest form of animal life. 

Protozoa are unicellular microorganisms (eukaryotes) that lack cell walls. They are found in 

marine habitat or soil, in freshwater bodies, symbiotic, some forms are parasites in other. 

organisms. Protozoa depends on nutrition, temperature, pH, and some depends on sunlight. 

Protozoa were defined as unicellular protists with animal-like behavior, such as movement. 

Protozoa were regarded as the partner group of protists to Protophyta, which have plant-like 

behavior, e.g., photosynthesis. The term protozoan has become highly problematic due to the 

introduction of modern ultra structural, biochemical, and genetic techniques, which have showed 

that the group does not form a clade as required by modern classifications.

Modern unicellular clades within Eukaryotes which may be viewed as approximately collectively. 

replacing the class of protozoa include: Excavata, Amoeba, Chromalveolata and Rhizaria. 

Protozoans are usually single-celled heterotrophic eukaryotes containing non-filamentous 

structures that belong to any of the major lineages of protists. They are restricted to moist or 

aquatic habitats (i.e., they are obligate aquatic organisms). Many protozoan species are 

symbionts, some are parasites, and some are predators of feces bacteria and algae. There are an 

estimated 50,000 protozoan species. 

The Protozoa are considered to be a subkingdom of the kingdom Protista, although in the 

classical system they were placed in the kingdom Animalia. More than 50,000 species have been 

described, most of which are free-living organisms; protozoa are found in almost every possible 

habitat. The fossil record in the form of shells in sedimentary rocks shows that protozoa were 

present in the Pre-Cambrian era. Anton van Leeuwenhoek was the first person to see protozoa, 

using microscopes he constructed with simple lenses. Between 1674 and 1716, he described, in 

addition to free-living protozoa, several parasitic species from animals, and Giardia 

lamblia from his own stools.

General Characters of protozoa: - 

• They are aquatic (fresh and salt water) free living parasitic, symbiotic or commensally. Usually microscopic with oval, elongated, spherical or ever-changing shape.
• They show cellular level of organization, where all the activities of the body are performed by a single cell.
• The protozoan cell body is either naked or surrounded by a non rigid pellicle. Cellulose is absent in the pellicle. 
• Some protozoans secrete shells of various inorganic compounds as external covers.
• They possess different types of locomotory organs. 
• They may bear flagella (flagellates), cilia (ciliates) or pseudopodia (scorodines). 
• Locomotory organs are absent in the parasitic forms.
• They are holozoic (animal-like) and feed largely on bacteria, microscopic algae and minute animals such as rotifers or on other protozoan’s including members of their own species. 
• Some are holophytic (plant-like); they contain chlorophyll and prepare their own food by photosynthesis (Euglena). 
• The parasitic protozoans devour on materials obtained from the hosts (Monocytes). 
• Some are saprozoic (subsisting on dead organic matter) and saprophytic (feeding on liquid food).
• The osmotic concentration of cell body (Osmoregulation) is maintained by one or more contractile vacuoles and these contractile vacuoles are help in excretion. 
• The excretory product is ammonia. 
• Asexual reproduction takes place by binary fission or budding. 
• Sexual reproduction is performed by the fusion of gametes or by conjugation. 

Examples: 

Free living- Euglena, Amoeba, Noctiluca, Paramecium, Elphidium (Polystomella) Parasitic Monocystis, Entamoeba, Giardia, Plasmodium, Trypanosome, etc 

• The single cell of the body performs all the vital activities. 
• Encystment occurs to tide over the unfavorable conditions and to help in the dispersal of race. 
• In certain animalcules, the life cycle is complicated and exhibits alternation of generations.

Habit and habitat: - 

Paramecium is occurrence in freshwater ponds, lakes, rivers and streams. It is also found in abundance in stagnant water bodies. 

Objective Question of Protozoa: - 

1) Coprozoic nutrition is found in: -

(a)Balantidium (b)Euglena (c) Noctiluca (d) Copromonas 

2)Holozoic nutrition is found in: -

(a) Paramecium (b)Balantidium (c) Euglena (d) Nyctotherus 

3)Saprophytic nutrition is found in: -

(a) Euglena (b) Leishmania (c) Amoeba (d) Monocystis 

4) Photoreceptor organ of euglena is: - 

(a) Stigma near reservoir (b) Stigma and Paraflagella Body (c) Chromatophore 

5) Lactoflavin (sensitizer) found in: -

(a) Eye spot (b) Paraflagella body (c) Golgi body (d) Mitochondria

6) Euglena is green in colour which is due to: -

(a) Chromatophores (b) Leucoplast (c) Carotene (d) Pyrenoid 

7) Euglenas belong to class: - 

(a)Phyto mastigophore (b) Zoo mastigophore (c) Rhizophore (d) None of these

8) Connecting link between plank and animal kingdom: - 

(a) Amoeba (b) Paramecium (c) Euglena (d) Opalina 

9)Which is oldest one of the animals: -

(a) Amoeba (b) Euglena (c) Opalina (d) Paramecium 

10)Osmoregulation in euglena Occur with the help of: -

(a) Vacuole (b) food vacuole (c) Contractile vacuole (d) none

11)Main Function of contractile vacuole is: -

(a) Nutrition (b) Excretion (c) Osmoregulation (d) Locomotion 

12)Digestion in protozoa is: -

(a) Intercellular (b) Intracellular (c) extracellular (d) all of these

13)Cytopyge is found in 

(a) Amoeba (b) Paramecium (c) Euglena (d) Trypanosome 

14) Tentacles are found in: - 

(a) Stylonychna (b) Ephelota (c) Euglypha (d) Trypanosome 

15)The presence of a long Flagellum and a short tentacle is the characteristic feature of: -

(a) Copromonas  (b) Chlamydomonas (c) Noctiluca (d) Euglena 

16) One of the characteristic features of Telosporea is: -

(a) Unicellular trophozoites (b) Multicellular trophozoites (c) Presence of shell (d) Presence of an eye spot 

17) Class sporozoan includes parasites protozoa in which locomotory organelles are: -

(a) flagella (b) absent (c) Both cilia and pseudopodia (d) of various type 

18)Locomotion in young sporozoan is by 

(a) Glidding (b) ciliary (c) amoeboid (d) euglenoid 

19) An example of sporozoan is: - 

(a) Elphidium (b) Monocystis (c) Difflugia (d) Vorticells 

20) Contractile vacuole is present in: -

(a) in marine protozoa (b) in parasitic protozoa (c) in fresh water (d) none of these

21) Which of the following do not have locomotory organelles: -

(a) Rhizopoda (b) Flagella (c) Ciliata (d) sporozoan 

22)Trichocysts are found in: - 

(a)ectoplasm of euglena (b) ectoplasm of paramecium (c) Both (d) none of these 

23)The mononucleate form is: -

(a) Balantidium (b) Chrysamoeba (c) stylonychia (d) Pelomyxa 

24) Trichomonas belongs to: - 

(a) protomonadia (b) dinoflagellate (c) schistoflagellata (d) polymastigina 

25)The characteristic feature of class Sporozoa is the presence of: - 

(a) flagella (b) parasitism (c) chlorophyll (d) none

26)The primary grouping of the protozoan is based on their: - 

(a) mode of feeding (b) locomotory organells  (c) both (d) none 

27) Class mastigophore include the protozoan in which locomotory organells is: -

(a)Lobo podium (b) flagella (c) cilia (d) absent 

28) The phylum protozoa is divided into sub-phylum on the basis of their: -

(a) nuclear structure (b) locomotory organ (c) Both (d) none of these 

29)The presence of slender pseudopodia with interlacing branch to form a network in the characteristic feature of the order: -

(a)Radiolaria (b) lobosoa (c) foraminifera (d) Mycetozoa 

30) Oder lobosa include: - 

(a) Pelomyxa (b) elphidium (c) globigerina (d) euglypha 

31) Chilomonas belong to the order: -

(a) chrysomonadina (b) euglenodina (c) Crypdomomadina (d) all of these 

32) Order Suctorida included: - 

(a) Trichonympha (b) Giardia (c) lophantonas (d) all of these 

33)Protenospongia is included in order: -

(a) Euglena (b) Rhizomastinoida (c) Choanoflagellida (d) all of these 

34)Volvox is included in order: - 

(a) Phytomonadida (b) euglenida (c) Chrysomonadida (d) none of these 

35) Ceratium is included in order: -

(a) Mastigophora (b) Dinoflagellata (c) Euglena (d) all of these 

36)Karyosome consist of two materials, what is the achromatic substance present in it?

(a)Plastin (b) Chromosome (c) Paramylum (d) None of these 

37) The shell of polystomella is made up of: -

(a) calcium carbonate (b) Silicon (c) all of these (d) None of these 

38) Cytopyge is found in: -

(a) Amoeba (b) Trypanosoma (c) Euglena (d) All of these 

39) The locomotory organelle of foraminifera are: -

(a) lobopodian (b) filopodia (c) axopodia (d) all of these 

40)which of the following protozoans is unlikely to have a contractile vacuole?

(a) Paramecium (b) Plasmodium vivax (c) Euglena (O all of these 

41)Grand old man of the intestine is 

(a) Amoeba (b) Giardia (c)Entamoeba (d) None of these 

42) The disease caused by the infection of Trichomonas :-

(a) amoebiosis (b) Kala-azar (c) Trichomoniasis (d) None of these 

43) 'Tripali stone ' is characterise presence of :- 

(a) Foramaniferian (b) Radiolarian (c) Actinosphaerium (d) None of these 

44)Which show endocommensal form in large intestine of anura :- 

(a) Opalina (b) Monocystis (c) Trypanosoma (d) none of these 

45)Balantidium in Housing the intestine of: - 

(a) Man (b) Pig (c) Sheep (d) fish (e) all 

Answer key: -

(1)d (2)c(3)a(4)c(5)b(6)a(7)a(8)c(9)b(10)c(11)c(12)b(13)b(14)b(15)c(16)a(17)b(18)a(19)b(20)c(21)d(22)b(23)b(24)d(25)b(26)b(27)b(28)b(29)c(30)d(31)c(32)a(33)c(34)a(35)b(36)a(37)b(38)b(39)b(40)a(41)b(42)c(43)b(44)a(45)e