KINGDOM
ANIMALIA
High Yield Notes
, NOTES
NOTES
KINGDOM ANIMALIA
INTRODUCTION TO
KINDOM ANIMALIA
The word ‘Animalia’ has a Latin STB: 33 phyla out of which 9 are
origin→ Anima = Breath/Soul major and the rest are minor
The most conspicuous phyla.
organisms are found in PTB: 29 phyla out of the total
Kingdom Animalia. phyla belong to subkingdom
Animals range in size and eumetazoa.
complexity from a merely Multicellular organisms have
microscopic parazoan evolved from protists at least
Trichoplax to the giant blue three times.
whale Balaenoptera that Definition of a true animal:
reaches a length of nearly 40 Eukaryotic, Multicellular,
meters and weighs more than Ingestive Heterotrophic
160,000 Kilograms. Organisms
True land-dwelling animals are Most animals are motile.
found in phylum Arthropoda
and Chordata. Development of Zygote:
Ancestors of animals → Animal- An animal starts its life as a
like protists/ protoctista i.e., zygote which is formed as a
Choanoflagellates result of fertilization.
About 1.3 Million species are It develops by a sequence of
included in Kingdom Animalia mitotic division which is known
The sponges (phylum Porifera), as cleavage and forms a
cnidarians (phylum Cnidaria), multicellular structure, first as a
and flatworms (phylum solid ball of cells called morula
Platyhelminthes) probably and then as a hollow ball of cells
represent the three separate known as blastula.
evolutionary lines. The blastula invaginates or folds
inwards, forming a gastrula
The other animal phyla probably
which has a hollow sac having
evolved from a flatworm or
an opening called a blastopore
flatworm-like ancestors.
(the place from where the
Kingdom Animalia is divided
mouth or anus forms).
into phyla.
Continuous division of cells
leads to the development of a
zygote into a young one.
1
PreMed.PK
, NOTES
Grade Radiata and Grade Bilateria
Two Kingdom Systems:
Organisms were initially divided
into two categories:
1. Metazoa (consisting of all
multicellular organisms)
2. Parazoa (Consisted of all
unicellular organism)
Parazoa:
It is the simplest sub-kingdom
Its animals lack tissues
organized into organs and they
have intermediate shapes and
are asymmetrical
Consists of phylum Porifera only
Eumetazoa:
Animals of eumetazoa have Radial symmetry
tissues which are organized into
organs and organ systems.
These animals include radially
symmetrical animals (Grade
Radiata)and bilateral
symmetrical organisms (Grade
Bilateria)
Grade Radiata:
Here, animals have radial
symmetry and all of them are
diploblastic
Consists of the simplest
eumetazoa i.e. Phylum Cnidaria
they have simpler organization
than others.
Their body parts are arranged
around a central axis such that
any plane passing through the
central axis divides the animals
into halves →Looks like they are
almost mirror images of each
other.
2
PreMed.PK
, NOTES Grade Bilateria:
All of the animals included in
grade bilateria are triploblastic
and all of them have bilateral
symmetry.
The right sides of these animals
are the same as the left sides
and they have a distinct interior.
Animals can be divided into two
equal parts by imaginary lines
only in one plane.
Animals have a differentiated
head at the anterior end and a
distinct posterior end. They also
have a distinct dorsal and
ventral surface.
Consists of all phyla except
Porifera (asymmetrical) and
Cnidaria (radial symmetry).
The Phylum echinodermata
have a developed bilateral
symmetry; their larvae structure
is bilateral while their adult form
is radial.
Bilateral Symmetry
3
PreMed.PK
ANIMALIA
High Yield Notes
, NOTES
NOTES
KINGDOM ANIMALIA
INTRODUCTION TO
KINDOM ANIMALIA
The word ‘Animalia’ has a Latin STB: 33 phyla out of which 9 are
origin→ Anima = Breath/Soul major and the rest are minor
The most conspicuous phyla.
organisms are found in PTB: 29 phyla out of the total
Kingdom Animalia. phyla belong to subkingdom
Animals range in size and eumetazoa.
complexity from a merely Multicellular organisms have
microscopic parazoan evolved from protists at least
Trichoplax to the giant blue three times.
whale Balaenoptera that Definition of a true animal:
reaches a length of nearly 40 Eukaryotic, Multicellular,
meters and weighs more than Ingestive Heterotrophic
160,000 Kilograms. Organisms
True land-dwelling animals are Most animals are motile.
found in phylum Arthropoda
and Chordata. Development of Zygote:
Ancestors of animals → Animal- An animal starts its life as a
like protists/ protoctista i.e., zygote which is formed as a
Choanoflagellates result of fertilization.
About 1.3 Million species are It develops by a sequence of
included in Kingdom Animalia mitotic division which is known
The sponges (phylum Porifera), as cleavage and forms a
cnidarians (phylum Cnidaria), multicellular structure, first as a
and flatworms (phylum solid ball of cells called morula
Platyhelminthes) probably and then as a hollow ball of cells
represent the three separate known as blastula.
evolutionary lines. The blastula invaginates or folds
inwards, forming a gastrula
The other animal phyla probably
which has a hollow sac having
evolved from a flatworm or
an opening called a blastopore
flatworm-like ancestors.
(the place from where the
Kingdom Animalia is divided
mouth or anus forms).
into phyla.
Continuous division of cells
leads to the development of a
zygote into a young one.
1
PreMed.PK
, NOTES
Grade Radiata and Grade Bilateria
Two Kingdom Systems:
Organisms were initially divided
into two categories:
1. Metazoa (consisting of all
multicellular organisms)
2. Parazoa (Consisted of all
unicellular organism)
Parazoa:
It is the simplest sub-kingdom
Its animals lack tissues
organized into organs and they
have intermediate shapes and
are asymmetrical
Consists of phylum Porifera only
Eumetazoa:
Animals of eumetazoa have Radial symmetry
tissues which are organized into
organs and organ systems.
These animals include radially
symmetrical animals (Grade
Radiata)and bilateral
symmetrical organisms (Grade
Bilateria)
Grade Radiata:
Here, animals have radial
symmetry and all of them are
diploblastic
Consists of the simplest
eumetazoa i.e. Phylum Cnidaria
they have simpler organization
than others.
Their body parts are arranged
around a central axis such that
any plane passing through the
central axis divides the animals
into halves →Looks like they are
almost mirror images of each
other.
2
PreMed.PK
, NOTES Grade Bilateria:
All of the animals included in
grade bilateria are triploblastic
and all of them have bilateral
symmetry.
The right sides of these animals
are the same as the left sides
and they have a distinct interior.
Animals can be divided into two
equal parts by imaginary lines
only in one plane.
Animals have a differentiated
head at the anterior end and a
distinct posterior end. They also
have a distinct dorsal and
ventral surface.
Consists of all phyla except
Porifera (asymmetrical) and
Cnidaria (radial symmetry).
The Phylum echinodermata
have a developed bilateral
symmetry; their larvae structure
is bilateral while their adult form
is radial.
Bilateral Symmetry
3
PreMed.PK
