1. Metamerism is characteristic of
a. Platyhelminthes
b. Mollusca
c. Porifera
d. Annelida
2. Animals/organisms floating on the surface of water are [CBSE PMT 1998; BHU 1998, 01]
a. Plankton
b. Pelagic
c. Benthon
d. Neritic
3. Body does not show any segmentation in
a. Frog
b. Cockroach
c. Earthworm
d. StarFish/Hydra
4. Radial symmetry occurs in [CPMT 1980; AFMC 1985; Haryana PMT 1995; CET (Chd.) 2003]
a. Fishes
b. Molluscs
c. Star Fishes
d. Sponges
5. Animals having well marked digestive cavity are included under [AFMC 1978]
a. Parazoa
b. Enterozoa
c. Mesozoa
d. Metazoa
6. An animal which comes out at night and hides during day time is
a. Diurnal
b. Nocturnal
c. Cursorial
d. Arboreal
7. Level of organisation in sponges is
a. Cellular level
b. Acellular level
c. Tissue level
d. Organ-system level
8. Cell aggregate plan is found in
a. Cnidarians
b. Sponges
c. Roundworms
d. Flatworms
9. Level of structural organisation found in Hydra and Jelly Fishes is
a. Cellular
b. Acellular
c. Tissue
d. Organ-system
10. A deuterostome animal is
a. Sea Anemone
b. Star Fish
c. Pearl Oyster
d. Cabbage Butterfly
Characteristics of Animal Kingdom
✓ About 1.2 million animal species are known
✓ Animals differ from one another in their habitat, level of organization, body plan, symmetry, body cavity,
germ layers, mode of locomotion and
various other life processes
✓ They are multicellular (metazoans) and
eukaryotic
✓ Animals lack cell wall
✓ The possess some type of skeletal support
✓ They exhibit levels of organization(cell, tissue, organ and system)
✓ Reproduction is by asexual or sexual means
✓ They are capable of locomotion
✓ They possess a nervous system
BASIS OF CLASSIFICATION
Animal body plan vary in
✓ Levels of organization
✓ Body Symmetry
✓ Germ layers
✓ Body Cavity
✓ Segmentation
✓ Notochord
LEVELS OF ORGANIZATION
Organ Level
✓ Tissues are arranged into organs
and the organs are associated to
form organ systems.
✓ Each system performs a specific
physiological function.
✓ E.g. Platyhelminthes to chordates.
Cellular Level
✓ Cells are arranged
as loose cell
aggregates.
✓ E.g. sponges
Tissue Level
✓ Cells are arranged into
tissues.
✓ E.g. coelenterates,
ctenophores
BODY SYMMETRY
Bilateral Symmetry
✓ Body can be divided into
identical left and right
halves in only one plane
✓ Annelids, arthropods,
vertebrates etc.
Asymmetry
✓ Any plane that passes through the centre
does not divide them into equal halves
✓ E.g. Sponges.
Radial Symmetry
✓ Any plane passing through the central axis of the body divides the organism into two identical halves
✓ E.g. Coelenterates,
ctenophores and echinoderms
✓ Refers to the similarity in shape, size and number of parts on the opposite sides of a median line
GERM LAYERS
Diploblastic Triploblastic
✓ Based on the number of germ layers, animals are 2 types- Diploblastic and Triploblastic.
✓ 2 germ layers- outer ectoderm
and inner endoderm.
✓ E.g. Sponges and Coelenterates.
✓ 3 germ layers- Outer ectoderm, middle
mesoderm and inner endoderm.
✓ E.g. Flat worms to mammals.
COELOM (BODY CAVITY)
✓ Body cavity or coelom is the space between the body wall and the alimentary canal
Eucoelomate
✓ A true coelom is
completely lined by
tissues derived from
mesoderm.
✓ E.g. Annelids, molluscs,
arthropods, echinoderms,
Chordates etc.
Acoelomate
✓ No coelom.
✓ The space between body
wall and digestive cavity
is filled with matrix
(parenchyma).
✓ E.g. Porifera,
Coelenterates and
flatworms.
Pseudocoelomate
✓ A body cavity that is not completely lined by tissues derived from mesoderm.
✓ Mesoderm is present as
scattered pouches in between the ectoderm and
endoderm.
✓ E.g. Roundworms.
SEGMENTATION
✓ Segmentation: Division ir differentiation of body parts into distinct portions called segment.
✓ Metameric segmentation: the body is externally and internally divided into segments with
a serial repetition of at least some organs. E.g. Annelida,
✓ Segmentation is mainly external in Arthropods
✓ Segmentation is mainly internal in chordates.
NOTOCHORD
• Animals with notochord are called
chordates and those without
notochord are called
non-chordates.
• Notochord is a mesodermally
derived rod-like structure formed
on the dorsal side during
embryonic development in some
animals.
• Non Chordates e,g: Porifera to
echinoderms.
ANIMAL KINGDOM-PROTOZOA
✓ Leeuwenhoek first studied Protozoans
✓ The name "Protozoa" was coined by Goldfuss (1817).
✓ The branch of biology which deals with protozoans is called PROTOZOOLOGY.
CHARACTERISTICS OF PROTOZOA
✓ Microscopic, unicellular eukaryotic organism.
✓ Exhibit protoplasmic level of organisation.
✓ Encystment generally occurs to help in
dispersal.
✓ Some exist as parasite or in a commensal
relationship with other organisms.
✓ Locomotory organelles are pseudopodia or
cilia or flagella or absent
✓ Reproduction is asexual and sexual.
✓ Presence of contractile vacuole for osmoregulation (present in free
living forms but absent in parasites).
✓ Nutrition — autotrophic, saprophytic, saprozoic
✓ Examples : Plasmodium, Monocystis, Paramecium, Euglena,
Chlamydomonas, Trypanosoma, Leishmania etc.
KINGDOM PROTISTA: PROTOZOANS
Amoeboid
Protozoans
✔ Presence of pseudopodia
for locomotion
✔ Marine amoeboids have silica shells
✔ Some of the amoeboids are parasites,
e.g. Amoeba, Entamoeba
Flagellated Protozoans
✔ Flagella for locomotion
✔ Free-living as well as parasitic
✔ Trypanosoma causes sleeping sickness.
Ciliated Protozoans
✔ Cilia all over their
body which help in
locomotion as well as nutrition.
✔ Have a cavity (gullet) that opens to
outside.
✔ Paramecium
Sporozoans
✔ Have an
infectious
spore-like stage in their life cycle.
✔ E.g. Plasmodium
(malarial parasite) .
It causes malaria.
PROTOZOA-AMOEBA
Characteristics of Amoeba proteu
✓ It was first discovered by Russelvin Rosenhof (1755)
✓ Habitat: Found in fresh water
✓ Pseudopodia for mocomotion type lobopodia.
✓ Lobopodia: Are fairly large and tubular with rounded tips.
✓ Contractile 'vacuole is present for osmoregulation
✓ Cytoplasm is differentiated into endosperm and ectoplasm.
Plasmalemma:
✓ Very thin, delicate plasma membrane
or unit membrane
✓ Have no cell wall.
Nucleus:
✓ Single, conspicuous, flattened and
somewhat biconcave
Nutrition: Holozoic
✓ Feeds by phagocytosis
Respiration And Excretion- Diffusion
Reproduction:
✓ Asexual Reproduction Binary fission and Multiple fission
Encystment:
✓ During unfavourable protective covering or cyst wall is formed.
✓ Helps in protection survival and dispersal
PROTOZOA-PARAMECIUM
Characteristics of Paramecium
✓ Habitat: Fresh water, er ponds, pools, ditches, streams, rivers, lakes, stagnant water etc
✓ Locomotion: It moves here and there with the help of cilia, which also functions as food capture.
✓ Nutrition: Holozoic, Digestion:
intracellular.
✓ Respiration and excretion: takes place by general body surface through diffusion
process.
✓ Reproduction: Asexually by transverse binary fission and sexually by conjugation.
Structure of Paramecium
✓ Pellicle- Membrane protecting the cell and maintain shape
✓ Cilia- Hair like structures to swipe in food
Collects food
✓ Feeding Apparatus: Peristome (Oral groove), Cytostome (mouth) adn cytopharynx
✓ Contractile vacuoles surrounded by radial
canal for osmoregulation
✓ Food vacuoles for intracellular digestion
✓ Nucleus: Large macronucleus and small
micronucleus
ANIMAL KINGDOM-PORIFERA OR SPONGES
Characteristics of Sponges
✓ Porifera show cellular level of
organization, Diploblastic,
Asymmetrical/radial, Acoelomate
✓ The study of sponges is known as
PARAZOOLOGY.
✓ Habitat: Aquatic. Sedentary, Solitary
or colonial.
Body Wall:
✓ Body wall perforated by pores
✓ Body wall with outer layer of flat cells
(pinacocytes)
✓ Inner layer of flagellated cells
(choanocytes or collar cells).
Canal System:
✓ Characteristic feature of sponges.
✓ By constant beating of flagella of
choanocyte cells, a water current is
produced which has fixed direction.
✓ All exchanges between sponge body and
external medium are maintained by
means of this current.
✓ The canal system helps in respiration,
circulation, excretion, nutrition etc.
Digestive System:
✓ System is absent, Water transport (canal
system) to gather food.
✓ It is intracellular and takes place inside
food vacuoles as in protozoans.
Circulatory system:
✓ Absent. Circulation by canal system.
✓ Food is distribution is brought by
wandering amoebocytes cells.
Respiratory system:
✓ Absent. Respiration by canal system.
✓ Exchange of gases occurs by
diffusion
Excretory System:
✓ Absent. Excretion by canal system.
✓ Ammonia is chief excretory waste,
its is removed through diffusion
Skeleton System:
✓ Possess an internal skeleton.
✓ May consist of calcareous or
siliceous spicules or of fine
spongin fibres or of both
Nervous system:
✓ Absent.
Reproduction:
✓ Occurs by both asexual and sexual
reproduction
✓ Asexual reproduction: Budding and
gemmules (Internal buds)
✓ Sexual Reproduction: Fertilization
internal.
✓ Development is indirect
✓ Highest degree of regenerating capacity.
CLASSES OF PORIFERA OR SPONGES
Hexactinellida
Example: Euplectella,
Hyalonema
Calcarea
Example: Scypha (Sycon),
Leucosolenia
Demospongiae
Example: Spongilla,
Euspongia,
Phylum – Porifera (Sponges)
Example: Sycon, Euspongia Spongilla
ANIMAL KINGDOM-COELENTERATA
Characteristics of Coelenterata
✓ Tissue grade of body
organization, radial or biradial
symmetry, diploblastic
organisms.
✓ Habitat: Majority are marine, a
few freshwater forms.
Body Cavity:
✓ Large body cavity/ gastrovascular
cavity/ coelenteron.
✓ Nervous system: Nerve net.
✓ Digestion: Extra and Intracellular.
✓ Only one opening in body—the
mouth, surrounded by a ring of
tentacles.
✓ Stinging cells/Nematocysts/Cnidoblasts present in ectoderm help in capturing prey.
✓ Respiration: Excretion through general surface of body.
Reproduction:
✓ Both Asexual and Sexual
✓ Fertilization external, Development is
indirect.
Alternation of generation/metagenesis:
✓ Alternate between Polyp and
Medusa
Polymorphism:
✓ Occurrence of two or more types of
individual in a single species during
life cycle.
✓ Polyp: Sessile, cylindrical body,
asexual zooid
✓ Medusa: Free swimming, umbrella
shaped, sexual zooid
CLASSES OF COELENTERATA
Anthozoa
Example: Metridium,
Alcyonium
Hydrozoa
Example: Hydra, Obelia
Physalia
Scyphozoa
Example:Aurelia
Phylum Coelenterata (Cnidaria):
Examples: Physalia, Obelia, Meandrina, Adamsia, Aurelia, Gorgonia, Pennatula, Hydra.
Physics Objective exams Mein Adam Aur George Ne Pen Hide kiya.
ANIMAL KINGDOM-CTENOPHORA
Characteristics of Ctenophora
✓ Also called walnut or comb jellies
✓ Tissue grade of body organization,
radial symmetry, diploblastic
organisms.
✓ Habitat: Marine, solitary and pelagic.
✓ Digestion is both extracellular and
intracellular
✓ Tentacles may be present or
absent.
✓ When present, the number of
tentacles are 2
✓ There are eight median comb
plates forming locomotor
organs, covered by cilia
✓ Sexes are not separate.
Reproduction takes place only by
sexual means.
✓ Fertilisation is external with indirect
development.
✓ Example: Ctenoplana,
Pleurobrachia, Cestum, Hormiphora
Phylum – Ctenophora (sea walnuts or comb jellies)
Examples: Pleurobrachia, Ctenoplana.
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