1. Phylum
    2. 1. Classification of Animals
    2. Protozoa
    3. Amoeba
    4. Entamoeba
    5. Paramecium
    6. Euglena
    7. Leishmania
    8. Trypanosoma
    9. Plasmodium
    10. Giardia lamblia
    11. Balantidium
    12. Porifera
    13. Coelenterata
    14. Platyhelminthes
    15. Nemathelminthes
    16. Annelida
    17. Earthworm
    18. Arthropoda
    19. Cockroach
    20. Mosquito
    21. Honey bee and Silk moth
    22. Mollusca
    23. Echinodermata
    24. Hemichordata
    25. Chordata
    26. Pisces
    27. Amphibia
    28. Frog
    29. Reptile
    30. Aves
    31. Mammalia
    32. Rabbit bone
  2. Animal Behaviour and Adaptation
    3. 33. Animal behaviour
    34. Animal adaptation
    35. Migration
  3. Developmental Biology
    4. 36. Development of Animals
    37. Development of Frog
  4. Human Biology
    5. 38. Tissues
    39. Sense organs
    40. Digestive system
    41. Circulatory system
    42. Respiratory system
    43. Nervous system
    44. Endocrine system
    45. Reproductive system
    46. Excretory system
    47. Skeletal system
    48. Basic concept of Immunology
    49. Human diseases
  5. Evolutionary Biology
    6. 50. Origin of Life
    51. Organic Evolution
    52. Theories of Evolution
    53. Evolution of Human beings
    54. Horse Evolution
Phylum
2. Protozoa
GENERAL FEATURES
Image 1
Fig. Well labelled diagram of Amoeba
Credit. Vecteezy
Science of Protozoa
Protozoology
Cell structure of protozoa
  1. Microscopic
  2. Unicellular or Acellular with one or more nuclei
Grade or organization
Protoplasmic level of body organization/ Acellular/ Molecular level of body organization.
Symmetry
Usually asymmetrical
Exception
  1. Giardia lamblia is bilaterally symmetrical.
  2. Volvox is spherical symmetrical.
CLASSIFICATION OF PROTOZOA
Characters
Sarcodina
Ciliata
Mastigophora
Sporozoa
Mode of Locomotion
Pseudopodia (Amoeboid movement)
Cilia (Coordinated, hair-like structures)
Flagella (Whip-like structures)
No locomotory organelles (Gliding or bending movements)
Habitat
Mostly freeliving found freshwater and marine environments, few parasitic and pathogenic
Mostly freeliving found freshwater and marine environments, few parasitic and pathogenic
Both free-living and parasitic, found in various aquatic habitats
Entirely parasitic, found inside host organisms
Reproduction
Asexual (Binary fission, sporulation), Some sexual (Syngamy)
Asexual (Binary fission), Sexual (Conjugation)
Asexual (Binary fission), Some sexual
Asexual (Sporogony), Sexual (Gamogony)
Nucleus
Usually one nucleus, though multinucleate forms exist
Two types of nuclei (Macronucleus and Micronucleus)
Usually one or two nuclei, can be multinucleate
Single nucleus in most species
Feeding Mechanism
Phagocytosis (Engulfing food particles)
Cytostome (Cell mouth) with food vacuoles
Absorption through general body surface or cytostome
Absorption directly from the host cells
Examples
  1. Amoeba
  2. Entamoeba
  1. Paramecium
  2. Balantidium
  3. Vorticella
  1. Euglena
  2. Trypanosoma
  3. Giardia
  4. Leishmania
  1. Plasmodium
  2. Monocystis
  3. Toxoplasma
1. Locomotory organ is absent in class

[IOM]

  • Mastigophora
  • Sarcodina
  • Sporozoa
  • Ciliata
2. Classification of Protozoa is on the basis of

[IOM]

  • Nutrition
  • Locomotory organ
  • Habitat
  • Reproduction
MODE OF LIFE
Free living or Parasitic
Free-living protozoans
  1. Amoeba
  2. Paramecium
  3. Euglena
  4. Volvox
Parasitic protozoans
Entamoeba
Colonize on Large intestine mucosa.
Giardia lamblia
Inhabits in crypts of Duodenum and Upper part of jejunum of man.
Balantidium
Resides in the Large intestine, similar to Entamoeba histolytica.
Plasmodium
Resides in Liver and Blood.
Leishmania donovani
Resides in Reticulo-endothelial system.
Trypansoma
Resides in Blood lymph, spleen, CNS and Cerebrospinal fluid.
Trichomonas
Resides in Genital tract and causes Vaginitis.
COLONIZATION
Majority of protozoans are solitary.
Exceptions
Volvox and Proterospongia are colonial.
BODY COVERING
Shelled protozoans
  1. Arcella
  2. Difflugia
  3. Elphidium
  4. Foraminiferans
Radiolarians
Continuous internal skeleton between ectoplasm and endoplasm is found.
LOCOMOTION
Protozoan class that does not carry its name after locomotory organ is Sporozoa.
Types of locomotory organs
Locomotory organelle
Protozoans
Pseudopodia (Lobopodia)
Amoeba
Flagella
  1. Euglena
  2. Trypanosoma
  3. Giardia
Cillia
Paramecium
NUCLEAR DIMORPHISM
  1. Nuclear dimorphism means nucleus varies from one to several.
  2. Paramecium shows nuclear dimorphism.
DIGESTION
Nutrition
  1. Holozoic
  2. Holophytic
  3. Saprozoic
  4. Parasitic
  5. Mixotropic: Euglena
Digestion is always intracellular.
OSMOREGULATION
  • •
    Osmoregulation takes place in fresh water protozoan with the help of one or two contractile vacuoles which is absent in marine and parasitic protozoans.
  • •
    When a fresh water Amoeba is kept in sea water, it loses its contractile vacuole but when a marine Amoeba is kept in fresh water, it develops contractile vacuole.
RESPIRATION
  • •
    Gaseous exchange takes place by diffusion through general body surface.
EXCRETION
  1. Excretion takes place through general body surface.
  2. They are ammonotelic. (NH3)
REPRODUCTION
Reproduction in protozoa may be asexual or sexual.
Asexual reproduction
Binary fission
Types of Binary Fission
Protozoans
Simple Binary Fission
Paramecium
Longitudinal Binary Fission
  1. Trypanosoma
  2. Euglena
Oblique Binary Fission
Ceratium
Note
Binary fission of a multinucleated protozoa into two or more smaller multinucleate daughter individuals is termed as Plasmotomy.
Budding
Budding is a modified binary fission resulting in a single or many daughter individuals in addition to the parent.
Examples
  1. Vorticella
  2. Ephelota
Sexual reproduction
Syngamy
Syngamy is fusion of two sex cells.
Conjugation
Conjugation is temporary contact of two individuals with nuclear exchange.
Note
  1. In most protozoa, sexually mature individual is haploid.
  2. Many protozoans form cyst which help them in overcoming unfavourable conditions and cause dispersal.
Note
Trichonympha
  1. Trichonympha is symbiotic protozoan found in gut of the termite helping in cellulose digestion.
  2. Trichonympha secrete Cellulose digesting enzymes.
Monocystis
Monocystis is parasite in the seminal vesicle of Earthworm.
Opalina
Opalina is found in Rectum (Small intestine) of Frog.

Multiple Choice Questions

1. The carrier of Trypanosoma in man is
  • Tse-tse fly
  • Mosquito
  • Sand fly
  • House fly
2. Holozoic type of nutrition is found in
  • Protozoa
  • Fungi
  • Dinoflagellates
  • Algae
3. Pseudopodia retain its movement due to change in
  • Viscosity
  • Pressure
  • Water movement
  • Pellicle
4. Disease caused by protozoa is
  • Kala-azar
  • Typhoid
  • Cholera
  • Whooping cough
5. Kala-azar is transmitted by

[MOE 2063]

  • Bed bug
  • Sand fly (Phlebotomus argentipus)
  • Mosquito
  • Pediculus
6. Protozoan class that does not carry its name after its locomotory organ is

[IOM 2004]

  • Flagellate
  • Rhizopoda
  • Sporozoa
  • Ciliata
7. Contractile vacuole of Amoeba and some other protozoans are related with
  • Digestion
  • Food collection
  • Water absorption
  • Osmoregulation
8. Entamoeba histolytica causes
  • Sleeping sickness
  • Malaria
  • Kala-azar
  • Dysentery
9. The infective stage of E. histolytica is
  • Trophozoite
  • Precystic stage
  • Cystic stage
  • Tetranucleate cyst
10. Euglena is
  • Ciliate
  • Sporozoan
  • Flagellate
  • Sarcodina
11. Primary basis of classification of protists is based on:
  • Locomotory organ
  • Size and shape
  • Mode of feeding
  • Mode of reproduction
12. Euglena belongs to the kingdom of:

[IOM 2069]

  • Monera
  • Protista
  • Plantae
  • Animal
13. In which of the following is fission not a method of sexual reproduction?
  • Plasmodium
  • Amoeba
  • Paramecium
  • All of the above reproduce by fission
14. Which of the following is not unicellular eukaryotes
  • Euglena
  • Diatoms
  • Dinoflagellates
  • Heliozoans
15. The commonest feature of Plasmodium and Paramecium is
  • Mode of nutrition
  • Locomotory organ
  • Reproduce by fission
  • Habitat
16. The commonest feature of Plasmodium and Paramecium is
  • Mode of nutrition
  • Locomotory organ
  • Reproduce by fission
  • Unicellular condition
17. Which of the following represents true fungus but like protists?
  • Albugo
  • True slime moulds
  • Yeast
  • Aspergillus
18. Excretion in Amoeba occurs through:
  • Lobopodia
  • Uroid protein
  • Plasma membrane
  • Contractile vacuole
19. Sporozoans have locomotory organs
  • Pseudopodia
  • Cilia
  • Flagella
  • None of the above
20. Promastigote of Leishmania is found in:
  • Gut of sandfly
  • Blood of man
  • CSF of man
  • Outside the host body
21. Which of the following is intestinal parasite?
  • Entamoeba
  • Plasmodium
  • Trypanosoma
  • L. donovani
22. Which of the following parasite is transmitted through kissing?

[IOM 2016]

  • Entamoeba gingivalis
  • Entamoeba histolytica
  • Ancylostoma
  • Ascaris
23. Which of the following parasites lives inside the gut of its host?
  • Giardia lambia
  • Trichomonas vaginalis
  • Trypanosoma tenax
  • Trypanosoma gambiens
24. Class of protozoa that lacks locomotory organs is:
  • Rhizopoda
  • Flagellata
  • Sporozoa
  • Ciliata
25. Infective stage of Giardia lamblia to human is:
  • Cyst
  • Egg
  • Trophozoite
  • Egg
26. The primary basis of Protozoa classification is
  • Excretion
  • Digestion
  • Nucleus
  • Locomotion
27. Pseudopodia is commonly found in
  • Amoeba only
  • Variety of protozoans
  • Protozoans and leucocytes
  • Amoeba and leucocytes
28. Contractile vacuole is present in
  • Marine protozoans
  • Fresh water protozoans
  • Both a and b
  • Parasitic protozoans
29. Protozoan group with two nuclei, macronucleus and micronucleus is

[KU 2012]

  • Flagellata
  • Ciliate
  • Sarcodina
  • Sporozoa
30. Causative agent of Malaria is
  • Bacteria
  • Protozoa
  • Virus
  • Helminth
31. Protozoans are considered animals because they are
  • Heterotrophic
  • Autotrophic
  • Carnivorous
  • Herbivorous
32. Pseudopodia is commonly formed in
  • Amoeba only
  • Variety of protozoans
  • Protozoans and leucocytes
  • Amoeba and leucocytes
33. What happens if a marine protozoan is transferred to a fresh water medium?
  • It bursts
  • It shrinks
  • It remains static
  • It enlarges but becomes normal again
34. Example of a bioluminescent protozoan is
  • Paramecium
  • Oplaina
  • Entamoeba
  • Noctiluca
35. Which of the following protozoans live in the gut of termites helping in cellulose digestion?
  • Plasmodium
  • Trichonymphya
  • Trypanosoma
  • Amoeba
36. Amoeba is placed in the phylum protozoa because of
  • Presence of cell wall
  • Presence of contractile vacuole
  • Phagocytic mode of nutrition
  • Acellular body
37. Type of pseudopodia formed in Amoeba is
  • Actinopodia
  • Lobopodia
  • Filopodia
  • Reticulopodia
38. The pseudopodia of Amoeba are locomotory organelles. These are tipped by
  • Pellicle
  • Hyaline cap
  • Plasma sol
  • Cuticle
39. Idea of conversion of sol into gel and vice versa in Amoeba was first given by
  • Mast
  • Best
  • Pantin
  • Hyman
40. Contents of a food vacuole in Amoeba are
  • First acidic then alkaline
  • First alkaline then acidic
  • First neutral then acidic
  • First alkaline then neutral
41. Amoeba captures its active prey by
  • Circumfluence
  • Circumvallation
  • Import
  • Invagination
42. If an amoeba is placed in distilled water, its contractile vacuole
  • Works faster
  • Works slowly
  • Disappears
  • Divides
43. An amoeba transferred from a container X to another container Y developed a contractile vacuole, but the vacuole disappeared again when the Amoeba was transferred back to container X. The container X and Y respectively contained:
  • Fresh and marine water
  • Marine and freshwater
  • Both contained freshwater
  • Both contained marine water
44. When a freshwater pond is about to dry, the likely response of Amoeba will be
  • Encystment
  • Binary fission
  • No change
  • Quick feeding
45. In unfavorable conditions, reproduction of Amoeba is by
  • Endomixis
  • Conjugation
  • Binary fission
  • Sporulation
46. Amoeba is called immortal and it is scattered all over the world due to the formation of
  • Spores
  • Regeneration
  • Binary fission
  • All of these
47. Amoebulae are the products of
  • Syngamy
  • Fragmentation
  • Binary fission
  • Multiple fission
48. Amoebic dysentery is caused by
  • Entamoeba histolytica
  • Amoeba proteus
  • Entamoeba coli
  • Entamoeba gingivalis
49. Which of the following has only one host?
  • Entamoeba histolytica
  • Trypanosoma gambiense
  • Taenia solium
  • Plasmodium vivax
50. The number of pseudopodia present in the trophozoite of Entamoeba histolytica is
  • One
  • Two
  • Many
  • None
51. Entamoeba histolytica in man is found in
  • Colon
  • Small intestine
  • Oral cavity
  • Stomach
52. How many metacystic uninucleate trophozoites are produced from a single infective cyst of Entamoeba histolytica?
  • 8
  • 1
  • 4
  • 2
53. Infective stage of Entamoeba histolytica is
  • Trophozoite
  • Precystic form
  • Metacystic form
  • Quadrinucleate cyst
54. The disease caused by Entamoeba gingivalis is spread through
  • Anopheles
  • Kissing
  • Air
  • Housefly
55. Reserve food in Euglena viridis is mainly
  • Fats
  • Starch
  • Paramylon
  • Both b and c
56. African sleeping sickness is caused by
  • Trypanosoma gambiense and transmitted by Glossina palpalis
  • Entamoeba gingivalis and transmitted by housefly
  • Plasmodium vivax and transmitted by tse tse fly
  • Trypanosoma lewsi and transmitted by bedbug
57. Trypanosoma finally invades
  • Cerebrospinal fluid
  • Tse tse fly
  • Culex
  • Sandfly
58. A person suspecting the infection of Trypanosoma should get examined
  • Urine
  • Stool
  • Blood smear
  • Saliva
59. Dum dum fever is caused by
  • Plasmodium
  • Leishmania
  • Trypanosoma
  • Entamoeba
60. Sleeping sickness is caused by
  • Entamoeba
  • Monocytes
  • Trypanosoma
  • E. coli
61. The secondary host of Trypanosoma for man is
  • Glossina palpalis
  • Glossina morsitans
  • Phlebotomus
  • None of these
62. Cell drinking may be technically expressed as
  • Pinocytosis
  • Diffusion
  • Phagocytosis
  • Osmosis