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
1. Classification of Animals
▢ GRADES OF BODY ORGANIZATION/ LEVELS OF BODY ORGANIZATION:
Image 1
Image 1
Fig. Acellular grade of body
organization in Amoeba
Grade of organisation refers to the levels in which the cells are arranged
❖ Protoplasmic grade/ Molecular grade / Acellular grade:
◉ Characteristics: All life activities within a single cell
◉ Organisms:
  1. Protozoa and Other unicellular organisms
❖ Cellular grade:
◉ Characteristics:
  1. Loose association or Aggregation of cells
  2. Slight division of labour
◉ Organisms: Porifera
❖ Tissue grade:
◉ Characteristics:
  1. Forms definite tissue structures
  2. Tissue is a group of cells having similar shape, structure and origin and perform specific function collectively.
◉ Organisms: Cnidarians
◉ Nerve net: Nerve cells and their processes form a definite tissue structure
❖ Organ grade:
◉ Characteristics:
  1. Different tissues are organized into organs
  2. Each organ is specialized for a particular function
◉ Organisms: Platyhelminthes
◉ Organs:
  1. Eye (👁️‍🗨️) spots
  2. Proboscis
  3. Reproductive organs
❖ Organ system grade:
◉ Characteristics:
  1. Organs are specialized to form system which perform specific body function.
◉ Organisms: Nemathelminthes to Chordata
▢ GERM LAYERS:
Image 1
❖ Diploblastic Animals:
◉ Layers:
  1. Ectoderm
  2. Endoderm
◉ Examples: Protozoa to Coelenterata
❖ Triploblastic Animals:
◉ Layers:
  1. Ectoderm
  2. Mesoderm
  3. Endoderm
◉ Formation: Cells of either ectoderm, or more usually, the endoderm give rise to a third germ layer, the mesoderm.
◉ Examples: Platyhelminthes to Chordata
▢ BODY CAVITY/ COELOM:
Image 1
Fig. A. Acoelomate, B. Pseudocoelomate, C. Eucoelomate
❖ Acoelomates:
◉ Organisms: Animals without coelom or body cavity
◉ Examples:
  1. Coelenteron in Coelenterata
  2. In Platyhelminthes, the region between the ectodermal epidermis and the endodermal digestive tract is completely filled with mesoderm in the form of a spongy mass of space filling cells called Parenchyma.
❖ Pseudocoelomates/ Blastocoelomates:
◉ Description:
  1. Cavities not entirely lined by peritoneum.
  2. Called blastocoel which may be a persistent blastocoel or derived from vacuoles within cells.
◉ Examples: Nemathelminthes
❖ Eucoelomates:
◉ Description: Cavities bounded on all sides by mesodermal peritoneum.
◉ Subtypes:
◈ Schizocoelous:
■ Characteristics:
  1. Schizocoelom arises from mesoderemal split.
  2. This body cavity is formed from blocks of mesoderm around the gut that enlarge and hollow out.
  3. All the schizocoelomates are protostomains.
■ Examples:
  1. Annelida
  2. Arthopoda
  3. Mollusca
■ Haemocoelomates:
● Description: Coelom filled with blood is called Haemocoel.
● Examples:
  1. Arthopoda
  2. Mollusca
◈ Enterocoelous:
■ Formation:
  1. Enterocoelom arises from outpocketing of the embryonic gut(endoderm).
  2. It is formed by outpocketings of the primitive gut that break off and form the coelom.
  3. All the enterocoelomates are deuterostomes.
■ Examples:
  1. Echinodermata
  2. Hemichordatata
  3. Chordata
1.

Schizocoel is the body cavity of

[BPKIHS 2005]

  • Mollusca

  • Echinoderms

  • Platyhelminthes

  • Annelids

2.

Coelom derived from blastocoel is known as
 

[BPKIHS 2008]

  • Pseudocoelom

  • Schizocoel

  • Haemocoel

  • Enterocoel

3.

Haemocoel is present in

[MOE 2064]

  • Flatworms

  • Roundworms

  • Segmented worms

  • Insects

▢ ANIMAL BODY PLANS:
❖ Cell aggregate body plan:
◉ Characteristics:
  1. Cells are loosely aggregated
  2. Intracellular digestion
◉ Organisms: Sponges
❖ Blind sac body plan:
◉ Characteristics:
  1. Single gastrovascular cavity opening i.e, Mouth
  2. Mouth present but anus absent
◉ Organisms:
  1. Coelenterata and
  2. Platyhelminthes
❖ Tube within a tube body plans:
◉ Characteristics:
  1. Body consists of two tubes, outer formed by the body wall and inner by digestive tract.
  2. Organs, body cavities and tissues are present between the two tubes.
◉ Organisms:
  1. Nemathelminthes onwards
◉ Subtypes:
  1. Protostomes
  2. Deuterostomes
Table: Differences beween Protostomes and Deuterostomes
Characteristics
Protostomes
Deuterostomes
Blastopore
  1. Mouth origin from blastopore.
  2. Mouth develops first in the embryo
  1. Anus origin from blastopore.
  2. Anus develops first in the embryo
Coelom formation
Schizocoely
Enterocoely
Cleavage
  1. Spiral cleavage
  2. Determinate cleavage
  1. Radial cleavage
  2. Indeterminate cleavage
Examples
  1. Annelida
  2. Arthopoda
  3. Mollusca
  1. Echinodermata
  2. Hemichordatata
  3. Chordata
1. 'Deuterostomia' are the animals in which blastopore of gastrula becomes
  • Mouth
  • Anus
  • Mouth or Anus
  • None
▢ ANIMAL SYMMETRY:
Image 1
❖ Asymmetrical:
◈ Characteristics:
  1. Body can't be divisible into two similar halves along any plane.
  2. Lack of polarity: There exists no clear differentiation along an axis.
◈ Organisms:
■ Protozoans:
● Exceptions:
⟣ Spherical symmetrical:
  1. Volvox
  2. Heliozoa
  3. Radiolaria
⟣ Bilateral symmetrical: Giardia lamblia
■ Adult sponges:
● Exceptions:
⟣ Radially symmetrical:
  1. Larva of sponges
  2. Sycon and Leucosolenia
■ Some molluscs:
  1. Gastropoda due to torsion
❖ Symmetrical:
Image 1
Fig. Spherical symmetry in volvox
◉ Spherical symmetry:
◈ Characteristics:
  1. Body resembles a sphere, suited for floating and rolling animals
  2. Lack of polarity: There exists no clear differentiation along an axis.
◈ Organisms:
■ Protozoa:
  1. Volvox
  2. Heliozoa
  3. Radiolaria
◉ Radial symmetry:
◈ Characteristics:
  1. Body can be divided into similar halves by more than two planes passing through one main axis
  2. Have oral and aboral sides
  3. Usually exhibited in animals attached to the substratum
  4. Like a cake being divided and sub-divided into equal halves and quarters.
◈ Organisms:
■ Sponges:
  1. Larva of sponges
  2. Sycon and Leucosolenia
■ Most of coelentrates:
■ Adult Echinodermata:
● Larval form: Bilateral symmetry
● Adult: Radial symmetry
◉ Biradial symmetry:
Image 1
Fig. Biradial symmetry in
Ctenophore
◈ Characteristics:
  1. Body can be divided into similar halves by two planes passing through one main axis
◈ Organisms:
  1. Sea anemones
  2. Sea walnuts (Comb jellies)/ Ctenophores
Note
◉ Sea anemones: Biradial symmetry > Radial symmetry
◉ Bilateral symmetry:
◈ Characteristics:
  1. Can be divided along a median Longitudinal or Sagittal plane into two mirrored portions (right and left halves)
  2. Bilateral animals are called Bilateria
  3. Strongly associated with cephalization
◈ Organisms: Flatworms to Mammals except some Molluscs and Echinodermata
1.

Which of the following pairs have the same body plan and symmetry?

[BPKIHS 2001]

  • Obelia and starfish

  • cockroach and frog

  • Hydra and earthworm

  • Pigeon and Leucosolenia

2. Radial symmetry occurs in
  • Porifera and Coelenterata
  • Arthropoda and Mollusca
  • Coelenterata and Echinodermata
  • Coelenterata and Platyhelminthes
▢ METAMERISM/ SEGMENTATION:
Segmentation is the serial repetition of similar organs, tissues, cell types or body cavities along the anterior posterior (A-P) axis of bilaterally symmetric animals
❖ Unsegmented:
◉ Characteristics: Body without a linear series of segments.
◉ Examples:
  1. Nemathelminthes
  2. Molluscs
  3. Echinodermata
❖ Pseudosegmented:
◉ Characteristics:
  1. Body with many false segments but are independent with each other.
  2. Body grows by addition of new segments from the anterior end.
  3. The body is divided into many segments known as Proglottids which are in different stages of maturation.
◉ Examples:
  1. Tapeworm
❖ True segmentation/ Metamerically segmented:
◉ Characteristics:
  1. Both with a linear series of segments, the segments are interdependent with each oter and work together.
  2. All segments are in same stage of maturation.
◉ Examples:
  1. Annelida (Polychaeta and Oligochaeta)
  2. Arthopoda
  3. Chordata
1. Metamerism is characteristic of
  • Porifera
  • Mollusca
  • Annelida
  • Echinodermata
▢ TYPES OF ANIMALS BY NITROGENOUS WASTES REMOVAL:
❖ Ammonotelic animals:
◉ Nitrogenous Waste: Ammonia
◉ Examples:
  1. Porifera
  2. Coelenterata
  3. Platyhelminthes
  4. Nemathelminthes
  5. Annelida
  6. Osteichthyes (Bony fish)
  7. Amphibian tadpoles (Frog tadpole)
Note
❖ Amphibian tadpoles:
◉ Frog:
◈ Hibernation and Aestivation: Uricotelic
◈ Regular Conditions: Ureotelic
❖ Crocodiles: Ammonotelic
❖ Aminotelic animals:
◉ Nitrogenous Waste: Amino acids
◉ Examples:
  1. Mollusca
  2. Echinodermata
❖ Uricotelic animals:
◉ Nitrogenous Waste: Uric acid
◉ Examples:
  1. Insects
  2. Birds
  3. Land snails
  4. Land reptiles (Lizard, Snake)
❖ Ureotelic animals:
◉ Nitrogenous Waste: Urea
◉ Examples:
  1. Mammals
  2. Chondrichtyes
  3. Semi-aquatic amphibians (Frog, Toads)
❖ Guanotelic animals:
◉ Nitrogenous Waste: Guanine
◉ Examples:
  1. Spiders
1. The excretion in birds and reptiles is:

[BPKIHS 2015]

  • Aminotelic
  • Ammonotelic
  • Uricotelic
  • Ureotelic
2. Animals in which nitrogen is predominantly excreted in the form of urea are

[KU 2015]

  • Ammonotelic
  • Ureotelic
  • Uricotelic
  • None of the above
▢ ANIMAL HABITATS:
❖ Aquatic animals:
Lives in water.
◉ Marine:
◈ Lives in sea.
◉ Freshwater:
◈ Lives in pools, ponds, lakes, streams and rivers.
❖ Terrestrial animals: Lives on land
▢ MODE OF EXISTENCE:
❖ Solitary:
◉ Characteristics:
  1. Lives singly.
◉ Examples: Sycon
❖ Gregarious:
Image 1
Fig. Gregarious nature
in sea squirt
Credit. Britannica
◉ Characteristics:
  1. Lives in group but don't help each others.
◉ Examples:
  1. Sea squirts
❖ Colonial:
◉ Characteristics:
  1. Lives in group and help each others.
◉ Examples:
  1. Ants
  2. Bees
  3. Wasps
❖ Free living animals:
◉ Characteristics: Lead an independent life.
❖ Symbiosis:
◉ Characteristics:
  1. Lives in an intimate relationship with other animals or plants.
◉ Parasitic (+, -):
◈ Characteristics: The symbiont (a parasite) receives benefits at the expense of the host.
◈ Parasite:
■ Ectoparasite:
● Characteristics: Parasite are external.
● Examples:
  1. Lice
  2. Tapeworm
■ Endoparasite:
● Characteristics: Parasite are internal.
● Examples:
  1. Liverfluke
  2. Roundworm
  3. Tapeworm
◈ Host:
■ Definitive host:
● Characteristics: Host in which parasite reach reproductive maturity.
● Examples: Mosquito for Plasmodium
■ Intermediate host:
● Characteristics: Host that is required for parasite development, but don't reach reproductive maturity.
● Examples: Man for Plasmodium
◉ Commensalism (+, 0):
Image 1
Fig. Euplectella
Image 2
Fig. Hydra
◈ Characteristics: Advantageous to one party (symbiont) but leaves other party unaffected (host).
◈ Examples:
  1. Spongicole living in Euplectella.
◉ Mutualism (+, +):
◈ Characteristics: Advantageous to one party (symbiont) but leaves other party unaffected (host).
◈ Examples:
  1. Zoocholera living in hydra.
▢ NUTRITION:
The means by which living organisms obtain the substances required for growth and the maintenance of life is called nutrition.
❖ Holozoic or Zootrophic nutrition (Animal-like):
◉ Utilize ready made solid food in the from of other organisms such as microorganisms, bacteria, yeast, algae, protozoans and small metazoans.
◉ Examples:
  1. Amoeba
  2. Paramecium
❖ Holophytic or Autotrophic nutrition (Plant-like):
◉ Obtain food by photosynthesis
◉ Examples:
  1. Euglena
  2. Volvox
❖ Saprophytic or Saprozoic nutrition (Fungi-like):
◉ Obtain the dissolved substances in the medium either through the entire surface of the body or through special regions.
◉ Examples:
  1. Monocystis
  2. Trypanosoma
❖ Parasitic nutrition:
◉ Get nourishment partially or wholly from the digested and decomposed substances of the food of host, either in holozoic or saprozoic manner.
❖ Mixotrophic or mesotrophic nutrition:
◉ Feeds by more than one method at the same or different times.
◉ Examples:
  1. Entamoeba histolytica which although feed holozoically, also absorb dissolved organic compounds through general body surface.
  2. Euglena feed by both holophytically and saprophytically.
❖ Coprozoic nutrition:
◉ Feed upon the faecal matter of other organisms.
◉ Examples:
  1. Copromonas is found in faeces of frog.

Multiple Choice Questions

1.

Which of the following pairs have the same body plan and symmetry?

[BPKIHS 2001]

  • Obelia and starfish

  • cockroach and frog

  • Hydra and earthworm

  • Pigeon and Leucosolenia

2.

Schizocoel is the body cavity of

[BPKIHS 2005]

  • Mollusca

  • Echinoderms

  • Platyhelminthes

  • Annelids

3.

Starfish belong to

[BPKIHS 2006]

  • Mollusca

  • Echinodermata

  • Annelids

  • None

4.

Which one of the following is a true fish?

[BPKIHS 2007]

  • Devil fish

  • Cuttle fish

  • Silver fish

  • Flying fish

5.

Salamander is

[BPKIHS 2007]

  • Reptile

  • Mammal

  • Amphibian

  • Bird

6.

Coelom derived from blastocoel is known as
 

[BPKIHS 2008]

  • Pseudocoelom

  • Schizocoel

  • Haemocoel

  • Enterocoel

7.

Which of the following is the smallest unit of classification?

[BPKIHS 2009]

  • Phylum

  • Variety

  • Genus

  • Species

8.

Neotype is

[I.E. 2003]

  • Nomenclature type from original material

  • Nomenclature type when the original is missing

  • One of the two or more specimens cited by author

  • New species discovered by scientist

9.

Most primitive organisms are

[I.E.]

  • Monerans

  • Protists

  • Fungi

  • Algae

10.

Complexity in classification is of

[I.E. 2005]

  • Prokaryotes

  • Unicellular eukaryotes

  • All animals

  • All plants

11.

Which of the following category contains organism least similar to one another?
 

[I.E. 2007, IOM 2069]

  • Class

  • Genus

  • Family

  • Species

12.

Haemocoel is present in

[MOE 2064]

  • Flatworms

  • Roundworms

  • Segmented worms

  • Insects

13. The excretion in birds and reptiles is:

[BPKIHS 2015]

  • Aminotelic
  • Ammonotelic
  • Uricotelic
  • Ureotelic
14. Gerontology is the study of

[IOM 2013, 2015]

  • Regeneration
  • Ageing
  • Death
  • Growth
15. Study of human race?

[BPKIHS 2016]

  • Eugenics
  • Phenology
  • Entomology
  • Ethnology
16. Ichthyology is the study of

[MOE 2012]

  • Fishes
  • Reptiles
  • Birds
  • Mammals
17. Animals in which nitrogen is predominantly excreted in the form of urea are

[KU 2015]

  • Ammonotelic
  • Ureotelic
  • Uricotelic
  • None of the above
18. The term biology was coined by

[KU 2013, 2012]

  • Aristotle
  • Theophrastus
  • Lamarck and Treviranus
  • Linnaeus
19. Metazoans without tissue grade organisation are called
  • Protozoa
  • Parazoa
  • Deuterostomia
  • Eumetazoa
20. Cell-tissue grade of organisation occurs in
  • Hydra
  • Sponge
  • Starfish
  • Liver fluke
21. Radial symmetry occurs in
  • Porifera and Coelenterata
  • Arthropoda and Mollusca
  • Coelenterata and Echinodermata
  • Coelenterata and Platyhelminthes
22. Bilateral symmetry is absent in
  • Obelia
  • Frog
  • Octopus
  • Mammals
23. Which symmetry is found in sea anemone?
  • Biradial
  • Asymmetry
  • Spherical
  • Pentamerous
24. All triploblastic animals are
  • Eucoelomates
  • Schizocoelomates
  • Radially symmetrical
  • Bilaterally symmetrical
25. Metamerism is characteristic of
  • Porifera
  • Mollusca
  • Annelida
  • Echinodermata
26. Which of the following phyla are included in Enterozoa?
  • Annelida, Mollusca, Porifera
  • Porifera, Arthropoda, Mollusca
  • Mollusca, Arthropoda, Hemichordata
  • Echinodermata, Hemichordata, Porifera
27. 'Deuterostomia' are the animals in which blastopore of gastrula becomes
  • Mouth
  • Anus
  • Mouth or Anus
  • None
28. An enterocoelomate invertebrate group is
  • Mollusca
  • Annelida
  • Arthropoda
  • Echinodermata
29. Coelom derived from blastocoel is known as
  • Haemocoel
  • Pseudocoelom
  • Enterocoelom
  • Schizocoel
30. The larva of Physalia is called
  • A Planula
  • An ephyra
  • A cydipped larva
  • A scyphistoma
31. Which of the following may exhibit biradial symmetry?
  • Ctenophora
  • Man
  • Radiolarian
  • Sponge
32. Symmetry found in Heliozoa is
  • Radial
  • Bilateral
  • Biradial
  • Spherical
33. Which one feature is common to leech, cockroach and scorpion?
  • Antenna
  • Nephridia
  • Cephalization
  • Ventral nerve cord
34. How many germ layers are found in a sponge?
  • One
  • Two
  • Three
  • Absent
35. Body is unsegmented in
  • Rana
  • Hydra
  • Metaphire
  • Periplaneta
36. Comb jellies belong to the phylum
  • Ciliophora
  • Coelenterata
  • Porifera
  • Ctenophora